u can be as redicules as u want to be. and if u can, say were the carector comes from:
4 me:
Bomberman
Chick Norris
Dr. Ocatonapus (the lazer collection... youtube)
Desposable Bottle Finger Man (Desposable Bottle Finger Man... youtube)
and... of course... your mother
uh... i did want the first one
but this is who i wanted
Nintendo Mii
Shadow the Hedgehog
Megaman
and Master Hand as a playble
I'd say:
Take the Pokemon out and substitute those characters for characters in the Megaman series. (Maybe Bass, Protoman, and Megaman; instead of Jigglypuff, Pikachu, and Pkmn. Trainer). I'd personally like to see Magnet Man as a playable character, (but most would disagree, he was just my favorite Dr.Wily robot).
Bass?....
Just kiddin' i know who he is an he is my FAVORITE robot/charecter
Its not a matter who should of been but who shouln't. (in my opinion)
Should of been left out:
Falco. (No need for 3 fox clones)
Lucas. (A charcter from a unrelesed game?)
Ice climbers. (Can't win with them if vs a lvl 1 com)
Diddy Kong. (would made a better assit trophy)
Should of been in it.
Shadow the Hedgehog
Mr. L (or at least one of Luigi's costume's or final smash)
Who should of been assit trophies:
Megaman X
Zero
Bowser Jr.
Should have been bosses:
Dr. Eggman
King Boo.
Its not a matter who should of been but who shouln't. (in my opinion)
Should of been left out:
Falco. (No need for 3 fox clones)
Lucas. (A charcter from a unrelesed game?)
Ice climbers. (Can't win with them if vs a lvl 1 com)
Diddy Kong. (would made a better assit trophy)
Should of been in it.
Shadow the Hedgehog
Mr. L (or at least one of Luigi's costume's or final smash)
Who should of been assit trophies:
Megaman X
Zero
Bowser Jr.
Should have been bosses:
Dr. Eggman
King Boo.
I support you
with the bosses and the Mr. L thing
but take out wolf and leave falco in
Kick that super stupid Jigglypuff out and put Waluigi in as a playable character rather than as some stupid assist trophy
your mother
My mom would have been the leader of the subspace army 
Kick that super stupid Jigglypuff out and put Waluigi in as a playable character rather than as some stupid assist trophy
your mother
My mom would have been the leader of the subspace army
is your mom really that evil?!?!?
Anyways what about Geno? he should be in
Hmm, I see Geno as a one-time-thing, simply because he was so inter-twined with the storyline of SMRPG.
I wonder what it would be like if Toad was playable?