Favourite's Ronaldinho, an absolutely unique card. He's easily the most fun to play with, good in the air, quick and creates space really easy, great ball control, first rate crossing and can finish brilliantly. Just wish I'd got him sooner.
The best has to be Gullit though, he can play anywhere and he's quality at absolutely evrything. Never loses a header and scores no matter where he plays. I used him at CDM at first with TOTY KDB as CAM and he was still class there, covers the whole pitch and always pops up with goals, but at CAM I think he's outscoring Ronaldo. He gets on the end of absolutely everything.
Special shout out to Vieira as well, he's equally as good at what he does but he doesn't shine as much as he does all of the dirty work. He wins the ball from anywhere due to the length of his legs and is impossible to knock off the ball. I think those three and Ronaldo are the ones who changed the game for me, all proper next level stuff.