I could only think of two characters.
1. Wario: Sure, his wackiness does give me a good laugh sometimes, but I can't shake off the impression he makes on me. He reminds me of some sleaze-bag couch-potato - and to top it all off, he's just downright gross.

2. Jigglypuf: I like her as a fighter....but not as a character. Out of all the hundreds of pokemon out there, I'm sure there could have been a better choice. As a character, there's almost nothing about her that makes her likable...let alone preferable over any other character (not including Wario).
However, with that said, I wouldn't want Jigglypuf taken from the game - she's an original, and I respect her for that.