How about linkle?

*Is a girl
*is cute
*isn't a clone
*would replace toon/young link spot on roster

Lyn/Lyndis - Fire Emblem
1. Game needs more FE reps
2. Game needs more FEMALE FE reps
3. Lucina is kinda redundant
4. To represent the first FE game released on the West

Knuckles - Sonic
- A "veteran" of SSF1 would be perfect as a third and possibly last Sonic rep

Speculated Characters:

Veterans - Mewtwo, Lucas, Little Mac, Ganondorf, Ice Climbers, Falco, Olimar, Snake, Pac-Man, Ike, King Dedede, Cloud Strife, Lucario.

Newcomers - Monkey D. Luffy, Simon Belmont, Knuckles, Zero, Shadow, Meowth, Chrono Trigger, Lip.

Mewtwo - YES After the fan demand he got in SSF2, he should be a lock, as an unlockable.
Lucas - YES Another highly requested character to come back as DLC in SSB4.
Little Mac - Maybe. I kinda agree on this situation. He was a highly requested character for SSB4 and got in, but SSF2 is a fan-game. The Devs could have picked up on his popularity though.
Gannondorf - He has to be. Locked in.
ICs - YES ( I Want My Main Back ) They need justice from being cut in SSB4.
Falco - YES Fox needs his trusty sidekick as an unlockable.
Olimar - Possibly With Distant Planet in the game, he should be guaranteed, but there could be a problem with coding the Pikmin in the game.
Snake- They already got the stage, hes garenteed. Agreed.
Pac-man - get rid of the assist trophy and he has a good shot Remember APEX 2015?
Ike - Idk , i feel like ichigo takes his spot there, id rather see a new FE Character. Lots of people say that. I agree. We'll have to wait and see.
King DDD - Its not complete without him... He should be locked in.
Cloud Strife - Very Possible. If hes not in the full version (Which i doubt that) he would definitely be one of the first expansions to come out. He should be locked in.
Lucario - I Wanna Say Yes, But Mewtwos a lot more unique as a character, this would be the same situation as cloud where expansions could be where he comes. This is a touchy situation where it involves two rival Pokemon. While both of them deserve to be in, it seems like one of them will get the cut. However, that DOESN'T mean only one will make the cut.
Luffy - YES, But i see him being a expansion unless they actually have him in the roster. Its hard to tell now especially since they finished the roster a while ago, and hes been starting to be the most requested since. 50/50.
Simon Belmont - Maybe A lot of people want him. It seems he would be a good fit.
Knuckles - They cant just have sonic and tails, that's not right. We need knuckles. Agreed.
Zero - Most Likely, kinda questioning it now. The only problem he has against him is the omission of X. However, he has been in games where X wasn't.
Shadow - I feel like hes in the roster, for all the hate he gets, he also get requested (2nd or 3rd Most Requested?) So we will just have to wait and see. It seems like the heavily requested characters will make it in. If Shadow gets in, it will most likely be an unlockable.
Meowth - Not Likely , But id like to see that happen. I could see him as a Poke Ball.
Crono Trigger - Now that cloud got out of this situation, it leaves Crono, and ill be honest I really want him...
But in the end i feel like he has a very slim chance.

The Ice Climbers and Duck Hunt Dog should get in as they represent Nintendo's early days.

Im Going to Play SSF2 Forever if The Ice Climbers are in the Game!

I agree because they have always been my mains from Melee! Plus their stage was hinted at being in SSF2...

Yeah and they also need Justice for being cut in Super Smash Bros for 3DS/ Wii U