I've only done Paris and the American ones but Paris is my favourite. Disney world is too big and busy, and California suffers from being cramped in. Every part metre square is concrete and has rides squeezed in. I miss the space and beauty of Paris, it's more important than most people recognise. There's something nice about a fully disnified campus in the middle of nowhere which makes you feel like you are away from real life. Even if Disney village is a bit naff, I somehow prefer it to walking out to Anaheim city centre or having to get a tram then a bus then another bus home from magic kingdom.
At a more temporary level paris has had great shows recently and my last visit to California had nothing on at the Hyperion and no fantasmic either. Paris does need some new rides though and especially coaster rides.