This is one of the reasons I chose a Moonlander over an Ergodox for my first split keyboard, the ability to fold the thumb cluster down to an angled position seemed like it'd be more natural. So far in the two months I've been using it I think I was correct about that (that said, when closer to flat the Moonlander's cluster is at a much steeper angle off the rest and is less than ideal)

Also likewise on thinking about a sculpted build, the rabbit hole is deep with these things. Redox Manuform is where I'm currently leaning, I like the extra keys and the thumb cluster looks a bit better. Unfortunately that means going full custom, since while a few vendors sell prebuild Dactyl Manuforms no one seems to do the Redox version.