For me, DCC captures everything I love - and ever loved - about D&D. It's fast, it's modular, it's easily adapted to damn near anything, and it's a blast to play.
In my games I also reskin the non-human player options and allow them as human classes. I've never had anyone who asked to play, say, a dwarven thief, but I'd be cool going the other way too.
The XP system is simple and glorious, and since it explicitly focuses on surviving encounters, not winning them, it encourages all kind of creative solutions rather than just a big fight every time. And I've seen that hold true true even for players who normally insist that D&D is a combat game and can't envision it being anything else.
The only real issue I have with the game is that it isn't a complete game in a sense; the magic items chapter, for example, has precious little in it other than advice to use the item lists from other games. Which is a shame, because the magic item stuff it DOES contain has the same kind of novel take on the game's development as the rest of the mechanics do.