Here’s the post with the soft over firm suggestion:
https://forum.mattressunderground.com/t/have-settled-on-a-latex-but-now-need-recommendations
Would 3" of 14 ILD Talalay would not work over 3" of 32 ILD Talalay? Would 28 ILD layer under it work better? I was trying to extrapolate from your example of using 3" of 19 ILD over a 36 ILD core, trying to keep the proportions similar. But you’re right, I don’t want to feel the firm layer through the soft layer, so I want to make sure that they work together.
The reason I’m strongly considering the DIY approach is because, from my understanding, the feeling of the 14 ILD Talalay latex is unlike any other material - it’s significantly softer than the 19 ILD, and it’s bouncier (and more resilient) than a similarly soft memory foam (I never liked the feeling of memory foam…). Additionally, I’m not seeing ANY mattresses that use that level of softness for their comfort layer - they don’t even have that as an option, the lowest I can find is the 19 ILD.
Ideally, I’d like to source 3 3" layers from mattresses.net (the 14 ILD and 2 other ones), and their mattress cover too - I suppose I could ask them if they’d build that for me? I really don’t feel terribly adventurous here, I just happen to want a specific thing that I’m not seeing anywhere, and ideally I’d like to avoid getting it through a mattress topper (especially since the mattress cover has wool quilted into it, and it would be a waste to just bury it under a topper). I do, however, want the expertise that comes from trying things and seeing how they work, and while I didn’t even know that “understanding mattresses” was even a thing until I discovered your website, now I absolutely must master that (not right away… but over time, I definitely want to). It’s not just because I really care about my own sleep (which I do), it’s also because I have to figure out appropriate mattresses for my kids as well, right now and as they grow. My 3-year-old girl has sleep trouble that seem very similar to mine, I’ve been suspecting that her mattress isn’t working for her for some time now, so I’m currently planning to try finding a source for a crib-sized (toddler bed) soft latex mattress for her - officially they only offer the crib size in extra firm (for the newborn babies), so that would have to be a custom order too…
But anyway… you are right, I definitely can’t predict how well a mattress would perform for me just by reading stuff (although I sure am going to try regardless!). So right now what I’m mostly hoping for is having as much knowledge and understanding as possible before going to the store, so that I’m clear on what exactly I’m testing, and what I expect it to be like, and can adjust my predictions based on what it’s actually like. And your input so far has been invaluable in helping me do just that 
Thanks again for all your help!
Tali
EDIT: I just discovered KTT enterprises from one of your threads. They happen to be located about 20 minutes from my husband’s family (whom we haven’t visited in a very long time). Do you have any idea if we could check out latex mattresses over there, rather than at a “regular store”? They basically carry what I was looking for, so if they’d be willing to let me test various configurations over there, that would be the most optimal solution for me, and would totally be worth the trip. Should I contact them to ask?