What i'm trying to say is that the community is unforgiving and expects ultra quality, even from an indie dev. If you make a small unoriginal and undiversified roster of 8 characters or so, people are forced to choose from limited roster and may not find ANY character they like, that is the danger, we are so used to Large rosters, that small roster looks like a cheap lowfi knockoff indie fighting game that is trying to compete with AAA budget fighting games. The more variety diversity the better, it will mean there will be a fighter 'for everyone', every gamer will find a unique character they like in that roster. This is a lot of balancing their health, the damage they do, and incur. Like a strong character, fast one less powerful, slow one more powerful, one with distance projectiles, one who needs to brawl up close, etc. You want your character roster to be all about equally capable, while still being different and having their peculiarities. Only through playthroughs will you uncover these unbalances. Refinement and balancing over and over, so that there are no 'unbalanced' character that is too strong (spam strong hits) or too weak (useless, KOed so quick), A dull flat experience does not help, great sound improves the experience. Solid Music and SFX are crucial for fighting gameplay impact/viscerality, thus for the 'fun' in the gameplay. Fighting games rely on visuals and SFX music. Graphics of course, if Graphics are ugly or cheap dull, it is a hard sell unless the fighting gameplay is Marvelous.

Thus, your game's character and graphics Art/Art design are truly important. Fighting games that are successes, having beautiful costumed characters, diverse, humans, creature, alien, robot, whatever, the game design of the roster is extremely important, your game's appeal depends on it : if your characters roster is uninspired and very plain generic, your game will suffer in terms of player interest/sales. Each character must be unique and not a clone of another (like Ruy, Ken and Akuma/Scorpion, Sub0, Reptile/Milena, Kitana clones), if they are clone you must differentiate them a bit. People complained of tiny roster, they want diverse roster, Large roster. 8 characters roster doesn't cut it anymore, fighting games have upwards of 20 to 40 characters roster PER game. You must create tons of intricate moves/animations/hit boxes/special fxs/hit fx, it's.long.

Other indie devs shun them as their first game to develop. 2D Fighting games are some of the most difficult games to make, if not the hardest.

Hi, just a 2 cents (am solo indie dev making a traditional 2.5D fighting game, over a year of development on it so far).

Unity engine fighting game