The UI is usuable as long as you use something like Dwarf Foreman to manage jobs on your dwarves. Without that, it's just horrible to figure out who has what skills and who is worth specializing on other tasks.
I strictly play vanilla and have had no problems. Once I get a 100ish dwarves I don't really worry about skill...they get it as long as they keep doing it anyway.
I hate to say it (Who am I kidding..) but you're missing out. Go read the wiki for a few hours first maybe? Or maybe I can just imagine everything perfectly from reading books? Damned if I know but it's super-awesome-fun-time-game (If you were Japanese).