The problem I in particular have with DF is that its control scheme is not only unorthodox (I use vim which is easily one of the top two text editors with unusual control schemes out there together with emacs...but that's a story in and of itself, and I use some other things on my PC that don't quite follow the usual layouts as far as keyboard-based stuff is concerned), but also that they're just not very 'empowering' like those two - sometimes it feels like I'm spending as much time wrestling with the menus and controls as actually performing higher-level actions within the game, which is...well, unfun at best. Not to mention just how inconsistent it is. Some menus you move through with ↑↓, others with +-, others with */. I get there is some slight differences in each of those but that's still adds complexity without also adding much depth in return, unless mastering difficult control layouts is your thing.
I get that DF's very user-unfriendly interface has built some sort of charm around it to some people, myself included in some capacity, but it's no mystery that it's up for a rework sooner or later - and the ability to rebind keys (and possibly even share said control schemes easily via some kind of raw/config files) would go a long way towards making the lives of both new and long-time players (power users, you could say) better, making things less confusing for the former and more empowering for the latter.
Some things just seem plain ass backwards to me sometimes. Why is resizing/moving the embark area done with ...UMKH/umkh (or some other control scheme which either way just seems plain arbitrary compared to WASD or even HJKL)?
I don't know how much of a spaghetti code the game is right now to make easily-rebindable controls relatively easy to implement, let alone being able to play around with the menus (though you could probably take some inspiration from things like Eve, WoW, GW2 and even non-video game examples like Krita and Foobar2000, which let you build-your-own-interface on the go, but that's a very dream world scenario and I don't know how applicable such approach would be to Dwarf Fortress to begin with), but it's not something that can be delayed forever, since it's more than just a quality-of-life thing.