Recently been listening to Mystical Ninja Starring Goemon music, and happy i came across this thread. I dunno if i'd describe Goemon as my 'favourite' game on N64, but hell, it stood out bigtime - in weird, bizarre, but all positive ways! fantastic humour, and typical Japanese humour too. I think he'd be an excellent candidate for a third party character. My only doubt he'd get in is Konami already having a representative.
Thinking of this though. Sakurai obviously doesn't want the Smash bros. franchise over-run with third party characters, but seriously, can you imagine just 3 character blocks on the select screen huddled together for the third party characters? Or even worse, spaced out in a bizarre order? Perhaps if Sakurai changed his mind and wants to surprise us with 5 third party characters (it would give the Character select screan a nice look to it, all the nintendo franchised characters in 2/3 rows, then 5 at the bottom or top of third party characters, nice number), it'd work...
BUT this is a goemon thread! I think if Konami were allowed another candidate, it'd have to be this. Simon belmont could be argued to be better, but lets face it, Simon is a traitor and went to Sony