akilpots

I think hard to generalize and no way to guarantee anything is craze free forever. I do think there is reasonable correlation though. Differences in the expansion rate of clay and glaze being the prime issue, followed by the long term reliance of the glaze to tolerate the slight inevitable difference. The fired COE is often a result of fully firing so a clay body or glaze not fired or fully melted may have a different COE than one that is. Just imagine a clay body or glaze under fired by two or thee cones, we would normally expect it to behave very differently than fully fired stuff because it is under fired. If both are under fired the same amount will their under developed  COE somehow be even between them?  While I think in the ranges you are working in, likely a decent indication, just firing hotter does not necessarily mean the glaze will have greater flexibility and could actually become harder and more prone to tensile failure.
I think your logic is reasonable, but believe it’s always best to test the the clay and glaze combination fired to cone.

I use 3 versions of the same clear- one clear, one tinted light blue, one tinted light yellow. I do all my decorating with underglazes so that's all I need. I tell my students with home studios to find 3 glaze combos that they really like- each combo may be two or more layered glazes (or even  single glazes if that's your style)- just 3 combos that they like and that kind of go together in style, and then use them over and over and perfect applying them so they can be really successful with every glaze load. 3 options will  be plenty to offer to people when you start selling, and will be manageable for keeping  different forms in stock in all 3 combos. It may take 6, 7, or 8 separate glaze to create all 3 combos, and that's manageable. Trying to maintain a dozen glazes in a home studio can get pretty crowded. Once you've perfect those 3, you can start testing other combos so that you can retire combos every few years and keep your offerings fresh.

i was trying out a bunch of different laguna clays as they are the closest supplier to me i found one that i liked at cone 6.
laguna RSMC
but mostly i've been using archie bray's Wally's Blush absorption rate is great at cone 6 and the fired color is very nice for the kind of work that i make.

i've been getting into spoon carving slowly...i also love to camp and spend time in the outdoors.

i was trying out a bunch of different laguna clays as they are the closest supplier to me i found one that i liked at cone 6.
laguna RSMC
but mostly i've been using archie bray's Wally's Blush absorption rate is great at cone 6 and the fired color is very nice for the kind of work that i make.

Here is  a view of the clay vein in my yard, and a lidded casserole fired to cone ten with white and rutile slip under a mild chrome glaze.  

i've been getting into spoon carving slowly...i also love to camp and spend time in the outdoors.

definitely multiple slips, glazes, and firings....and a lot of testing. reminds me of tony marsh's crucible works. and some of jim malone's textured works. there's a good goldmark gallery video on jim malone where you can see him making some of these textured pots. he's applying dry clay to the surface of a pot while it's still wet on the wheel.
https://www.artsy.net/artist/tony-marsh?page=2
https://www.goldmarkart.com/collections/mike-dodd/products/mike-dodd-medium-textured-vase-cer-md-4154-s

Liner glaze, translucent white.
Clear blue, variegated green, red, variegated blue ...uhhm... teal blue.
Six!
There's scrap glaze, spills and wipe ups, wash offs, and such, it adds up after a while; when there were a couple gallons, I sieved and adjusted it.
It's gray-blue, light gloss.
The seven colors exhibit a range, depending on the clay, firing, and whatever may be fuming nearby in the kiln.
I use seven underglaze colors, all Speedball.
Some yellow would be nice, maybe via adding stain to the liner glaze.
This year I want to get Faux Celedon (Selsor's) back in the mix...
Down the line I expect to simplify. Each recipe is unique.
I'll typically use three or four colors in a glaze load.

I try to keep to five glazes in my own practice. In recent years, it’s been 2 base glazes with different colourants in them, and that will get you a lot of possible variation to work with. If you try to have too many glazes, it gets overwhelming fast. 
10-12 glazes is a roster you’d expect to see in a group studio or some other teaching environment, and it gets complicated to find that many that will work together well, without any of them being a PITA.

I use 4 main glaze colours for dipping glazes, all made from one base plus a clear liner, these are in 5 or 6 gallon buckets plus an accent glaze that is just a small container of glaze. When I used to spray glazes I had more glazes but could mix up smaller amounts of them since I didn't have to have a big bucket to dip them in. I find that using less colours makes a more cohesive looking display, I don't try and please everyone by offering every colour under the sun.

For most of the 20+ years I’ve had my basement studio, I’ve been using the same 3 base recipes. A dry matte, a semi-matte, and a glossy base. I have 1 variation on the dry matte, 2 variations of the semi-matte, and 2 variations of the glossy. Which equals 5 total. Which means I totally agree with your goal to keep 5 glazes. 
I also agree with @Marilyn T that having fewer glazes is beneficial to you, in terms of artistic growth. 

For functional glazes I have two ^6 base glazes that fit the clay I am using and then I have small containers of accent glazes.  I add stains/oxides to the base glazes to get the colours I want. I mix these base glazes into 5 gallon buckets and put a dolly under them to move them around my small studio space. Finding a suitable base glaze involved a lot of testing.  
I've gone the other route where I had up to 30 different glaze buckets,  but ended up realizing I was wasting a lot of materials and space to find the glazes I wanted to use.  For my present clay, only 2 out of 30 were a good fit and they only worked with the oxides in it -- with the oxides removed or different oxides -- they pinholed.   For the previous clay I used, none of them were a good fit (they all had delayed crazing).
I don't make non-functional work but if I did I would have as many glazes as I needed to create the style(s) I wanted.  Less options make it easier for you to find your voice.  

i've been getting into spoon carving slowly...i also love to camp and spend time in the outdoors.

i've been getting into spoon carving slowly...i also love to camp and spend time in the outdoors.

i've been getting into spoon carving slowly...i also love to camp and spend time in the outdoors.

Appreciate the people who have shared their recipes for a clear glaze. Getting a well fitting clear is one of the harder glazes to come up with.
For those new to mixing their own glazes, be sure to test the glaze for FIT before making up a big bucket. Glaze fit to a claybody is no different than fitting a pair of jeans. What fits my body won't necessarily fit everyone else's body. If you use a high expansion glaze on one side of a pot and a low expansion one on the other there is a good chance of the pot dunting / cracking.
If someone is looking for a clear glaze to use with or over stains or underglazes or some specific colouring combinations (like chrome tin pinks, reds, purples etc) then you need a specific type of clear glaze that is hospitable to the colourants. 

I've been working on this simple cone 6 glossy base using the cheapest materials at my supplier. also developed during matt katz's course.
https://glazy.org/recipes/420048

@ChristopherW
Ok I’ll take a shot. This was a favorite in 2018 and has been tested and used for a studio clear for several years I know of. Samples in dishwasher forever. Actually moved to new dishwasher as old one wore out. Test piece going on approx 800 wash cycles. It’s Gerstley so not so much a favorite anymore. Glazes often don’t travel well but you are welcome to it. Hope it works for you. This is one of those glazes developed taking the Katz course. The spreadsheet is his, but we have written permission by him to automate the sheet and redistribute. I think he has a new free excel sheet as well. Don’t forget use the 100% batch column.

I've been working on this simple cone 6 glossy base using the cheapest materials at my supplier. also developed during matt katz's course.
https://glazy.org/recipes/420048

there is a new edition out which is much cheaper.

An additional thought on Rhodes: he wrote several books, Clay and Glazes may be the most well known but he also wrote "Stoneware and Porcelain" and "Pottery Forms".
Our high school library had all three books and I poured over them endlessly as an impassioned wheel thrower. What made Pottery Forms so unique was that Rhodes often showed pottery shapes in profile. Meaning...he would cut the pot in half to show the wall thickness. That really sent home the message that a well thrown pot has an even thickness clay wall. (To prevent cracking, mostly, and warping.) I don't think too many other books had this element? 
What the profile shots also did was send home the message that crafting a good pot involves two processes: throwing the pot and trimming the pot.
 

For 33 year I had used my 3,00 lbs of Kingman feldspar that ran out in 2023 just when The Custar shortage (mine is in bankruptcy and will reopen in future) hit.
I had 4 bags stashed so it was not an issue yet but in last two months I picked up this stash and now will last my lifetime (1,000lbs  in total)
I traded a some moblilezer wax to an old potter friend for a new old stock bag real spodume  from 20 years ago (white bag  in photo)
I'm back to being ok with a potash feldspar and its one less thing to consider.

And here we come to it, the rub. 
Glazy has been a godsend to me, and I’ve yet to see anything bursting that bubble. I learned glaze chemistry and calculation thirty years ago in college, and used it loosely, only to evaluate recipes. Now, as then, I rely heavily on materials knowledge and gross ratios to come up with what I believe will work. Glazy allows me to put my guesses into a context of what has worked in other places for other people, and reduces (not eliminates) the testing. For materials that don’t have a published chemical analysis, or materials that have the same name but varying compositions (this talc vs. that talc, “ potash spar,” “boron frit,” or my local clay) there’s still guesswork. 
It takes much less effort to arrive at a data point that before would have been tedious to find, even with previous glaze calculation software. Glazy rests on the shoulders of everything that came before it and I don’t discount that, but we live in good times. Three cheers for Derek Au. 
I, like @Roberta12, look for that sweet spot on the UMF chart, nudge my glazes towards it and wait and see how the pots look after a few years in my kitchen. The only faster way to test seems to be alternating baths in strong alkali and acid (good old lye and that potent 30% vinegar @PeterH mentioned in another post). Like the weatherman, we haven’t arrived at perfect prediction, but it’s a lot better than it used to be. 

+1
Linda Arbuckle quote below regarding glaze calculation that I think pretty much sums it up for me:
"The purpose of glaze calculation is to determine the total amount of each element present in a glaze, and the proportions relative to each other. With that information at hand, it is possible to calculate materials substitutions, revise melting points, and do other useful calculations. In the end, testing is the final proof, but unity molecular formula gives you a more informed method of choosing what to test."
Are there qualifiers to interpreting the figures with glaze calc, yes of course there are. 
Glaze calc is another tool in the toolbox, one that can save a lot of work and material waste. I also use Limit / Target Charts, they aren't written in stone either but combined with UMF they can be a pretty good indicator if a glaze is worth mixing up and testing. An overload of boron, for example, might make a pretty and interactive glaze but I do question it's durability. Lots of lithium, I'm going to be wary of shivering. High level of sodium and / or potassium, odds of crazing are going to increase. Low alumina and / silica, glaze is not going to be durable regardless of flux ratio.  And so forth.  
Recently there have been a few materials that have become unavailable to potters, Custer, Gerstley Borate, some talcs plus the EPK shortage. Looking at the UMF for any of these offers a way to find alternative materials and or a combination of materials that can be used in place of ones lost and bypass a lot of the trial and error testing.