Hm, mine will be either Pit or Dr. Mario, followed by Bowser and Dedede. Liking Wii Fit Trainer as well. In the end though, while those will be my best ones I'll learn to use everyone to some degree, same as I do in any fighting game I pick up.
I'm just glad to FINALLY get this blasted new game. So very, very, VERY tired of Melee. Brawl, I loved that, and the original, but Melee.... thanks, as usual, to the community (Fox only, Final Destination!), what started as me loving it eventually ended up instead being me loathing it. Which just makes it 2000x more irritating that it's been the one to show up at events everywhere, bah. But this new one so far is looking to be better than both. I'll be glad for the Wii U version though; the 3DS one is great and all, but that damn analog stick....