I LOVE Fighting games. ok though to be fair I don't have the time to play them as much.
SF2 New Challangers, SFA 1 and 2, SF3 and SF4 are my Favorite Capcom.
I love Guilty Gear..... drooooool on the linking system. If I drooled anymore I think I would get kicked off the site :D. I've played a lot of the others MK, KoF, Samurai Showdown, Karateka(yes the original Figher), Gladiator, Smash Brothers series, Play Station All Stars, some I can't even remember the name of, Marvel Vs (capcom, Tatsunoku?), X-Men, SF vs X-Men. Clash of Champions and whetever else I'm missing. Though ihaven't played SkullGirls, blueblaze and persona4. I've been staying a way from Fighters these days do to my addiction to fighters :D and there odds to destroy my family :D
Though to be honest I like the Team Fighter a lot less. I play the Vs series, but I don't like them that much. It would be nice to play an optional 1 Character mode.
Anyways. Your website indicates this is a community of gamers making 0 budget game. ie no pay until the game is out and selling. But your limited tot he PC market. Which isn't really the most robust market for fighting games.
Also your being way to ambitious to launch with 20 characters. You should launch with 12, offer free up to 20 as they are developed then charge for more past that.
Keep in mind that the original SF only had 1 Playable Character, where as the rest had very limited moves to make them not playable. SF2 let you only play 8 Characters. then unlocked the bosses later for 12. Then only in SF2:NC did they offer 4 more for a roster of 16.
So I really suggest you offer 4 with an early access to test the waters. Launch with 8 for a Beta. 10 to 12 for a release version. release 2 at a time while continuing development up to 20. Then start charging DLC.
ok as for Online. This needs to be ironed out from day 1. If you don't build this into the game engine from the start. Don't do it at all. Also since your using C2 programmers you using C2. Wich means you need to consider what C2 can do for networking and your own needs and I'm going to lay them flat.
1. For online action fighters(like all listed in the OP) you NEED UDP based communications. Right now the only way to do that is to use NodeWebkit. This means it's PC only game and likely will never recieve a C2 to Wrapper Console port for years to come.
2. C2 does not have a robust networking api right now. Who ever you get is going to be putting a lot of work into both the game and building the networking plugin.
and finally you mentioned something about already having an investor?