Actually, I don't think Rare would let Nintendo use it's characters either. (Donkey Kong was Nintendo's in the first place.) Anyways, here's my version...
Normal Characters:
(All of the playable characters from the original, including the secret ones, plus...)
Toad(A-Punch, B-Spore, Down+B-Vegetable Toss, Up+B-Tornado jump)
Kooper(A-kick, B-shell shot, Up+B-Dizzy Shell Tornado, Down+B-Fire Shell)
Jeff(A-Pop Gun[short range], B-HP Sucker, Down+B-Counter Psi Unit[reflects attacks], Up+B-Gaia Beam)
Azumaril(A-kick, B-Water Gun, Up+B-Hydro Pump, Down+B-Rain Dance[Charges power])
Venasaur(A-Vine Whip, B-Razor Leaf, Down+B-Body Slam, Up+B-Stun Spore)
Deku Link(A-Spin, B-Bubble, Up+B-Deku-Flower Tornado, Down+B-Deku Nut)
Goron Link(A-Punch, B-Roll, Up+B-Shockwave Pound, Down+B-Place Powder Keg)
Zora Link(A-punch, B-Boomerang, Up+B-Backflip Slash, Down+B-Magic Shield)
(NOTE: Link would be changed to Kid Link from Majora's Mask)
SECRET CHARACTERS:
After beating a game in any of the difficulty settings, you get to battle for a new character and his stage. (NOTE: You get Poo, however, from completing all of the bonus stages.)
Super Easy=King Dede(A-Mallet, B-Swallow[doesn't get power, just slowly does damage], Up+B-Hammer Throw, Down+B-Megaton Punch)
Easy=Mewtwo(A-Tail Swipe, B-Psychic Blast, Up+B-Psybeam, Down+B-Swift)
Normal=Bowser(A-Slash, B-Fire Breath, Up+B-Chain Chomp throw, Down+B-Spikey Shellshot)
Hard=Skull Kid/Majora(Okay, he'll need a bit of explaining. When he transforms, it's only a quick puff of smoke and turns back, none of the dramatics from the game. A-Smack, B-Turns into Majora's Incarnation and charges quickly into his foe, Up+B-Launches Majora's Mask, and pilots it towards his foe, Down+B-Turns into Majora's Wrath and unleashes one of those spiked bombs.)
Super Hard=Golden Mario(All but one of his moves are the same, but do much more damage. That one is that fireball is changed to hammer throw, which travels quicker and does more damage. Golden Mario is also slow.)
Poo(A-Kung-Foo Chop, B-Transforms into a random character for a limited time, but takes damage when he changes back 30 seconds later. Up+B-Sword of Kings, Down+B-Meditate[slowly heals damage, if undisturbed])
Arenas
Mario's Pad(Mario and Luigi)
Bug Catcher's Forest(Pikachu and Jigglypuff)
Metroid(Samus... wasn't Metroid the planet in one of the games...?)
F-Zero Race Track(Captain Falcon)
Pop Star(Kirby)
Clock Town(Link in all forms)
Onett Town(Ness and Jeff)
DK's Tree House (Donkey Kong)
Outside Peach's Castle(Toad)
Koopa Village(Kooper)
Indigo Plateau(Venesaur and Azumaril)
Yoshi's Island(Yoshi)
Fox's Ship(Fox)
*Secret Levels*
As I said, you would get these in addition to the secret characters when you beat a "challenge match".
Super Easy=Dede's Boxing Ring
Easy=Secret Cave
Normal=Bowser's Castle
Hard=Inside the Moon (the room you fight Majora in...)
Super Hard=Mario Championship Battle(This is inside a crystal cavern much like the one you fight Metal Mario in in the original, only there is a crowd of Mushroom folk cheering one of you on in the background, as well as a giant Mario Statue, which is giving the "peace" sign, and the Nintendo logo floating in mid-air above.)
...and that about wraps it up...
