Oh don't get me wrong, this particular character is as dumb as rock. In fact I don't think he has EVER talked in the entire series. But hey, if we can take stupid fighter like Jigglypuff, then all we means we can have Crash!
By now some of you are probably wondering what Crash can really do. Let get one thing straight, he may be legally retarded but by no means is he unarmed. Besides his normal attack (punch punch kick kick..the regular) His special moves would actually be funnier than most. For example I can see his (down+special attack) being a body slam just like in the game.
His smash attack would also be uniquely funny. Remember Aku Aku (that little flying Tiki mask that was your practically best friend in the game)? Well, just like in the game, if he collect more than three of these little guy, he goes all gold chrome and insane like. I mean it the equivalent as Super sonic except on crack. That would totally be his smash attack. He may be stupid, but you best be fearing him buddy.
On a side note once more, Dr. Neo Cortex would be a perfect candidate for an assist trophy, something evil right?
Sora
This one sadden me the most out of all of them. Why? Because this will never ever, ever come about. Why ,Square Enix, wont you let Sora join the roster? Why cant we all just get along?
Now I couldn't possibly picked a final fantasy character because of how weird it would look on Brawl (I mean no offense., he a good character and all but Snake looks way out of place in Brawl).
Sora and friends are the exception to this rule because of the more laid back kind of tone in the game (well at least compare to final fantasy). But don't let the laid back tone of the game fool you, Sora is more than capable to dish out the pain in Brawl. Not including his arsenal of magic spells or his summons (which were useless in my opinion), his main weapon and the source of his true power are his keyblades. His story is far more complex for me to mention here even as a short story. That Square Enix has a good habit of making wicked storylines. Look it up on Wikipedia or something..
Right, down to his moves. His moves would be a lot more memorable to fans of the game, using techniques like "Ragnarok", "Sonic Blade" and finally "Strike Raid".
What would make me really happy, is his Smash attack. The Final Form. 
Now if you ever seen his attacks in this form, you know what to expect of him. I would hate to be the poor fighter who gets hit with this attack. Just go on YouTube or something and look this up. You know exactly what I'll mean.
On a side note* Kairi and Riku would be awesome assist trophies in brawl.
Note~
These last 4 characters are far less known then the first five. Some people would recognized some, other wont. Nevertheless these character would have made perfect candidate for Brawl.
Hell, if they have Mr. Game and Watch, then they can certainly have these characters.
Viewtiful Joe
If anyone played the game Viewtiful Joe, they would already know how much of a awesome character he is.
He would have to be according to the game he was in. One day, Joe and Silvia (his girlfriend) were watching a movie and what not right? Well for whatever reason an evil villain named Jadow (this whole game is very cliché just so you know) kidnaps Miss Silvia and takes her into a movie. With the help of Captain's Blue V-Watch (and saying the word “Heshin”) transform Joe into a super hero. Thus this fighter is born.
This guy was made to Brawl in my opinion. He already got down all types of moves. His special moves would have to be the techniques he learns in the game.
His smash attack could have the potential to be one of the best if he was made into Brawl. For example he could use the slow Zoom and the Red Hot One Hundred" on a single enemy or use any of the power he has.
With his trademark "Henshin-a-go-go, baby!", matrix-like moves combined style no other contender could match..
I could definitely see be the top favorite character for a lot people.
Rayman
You would expect some kind of sill story from this character, but to be honest there really isn't. Almost all stories (with the exception of one game apparently Ubisoft didn't give crap about) says that one day he was found by fishermen on a beach by the Sea of Lums. The fact that this guy has absolutely no history doesn't get to him at all.
