Things are pretty difficult to see and a lot of the time I can't tell if I'm hitting them or getting hit. Maybe try slowing down the pace of the game a bit and adding hit lag for every hit like most fighting games do ( i.e when a character hits another there is a brief time where the impact is played out to both accent the animation and allow players to see what they were hit with).
Also things get pretty hard to play when you are fighting the same character. Maybe add a symbol or arrow or something to show the player who they are controlling to help deal with this.