Agreed. Compile a comprehensive list of everything a player could do in any given situation in a traditional fighting game of your choosing and map them out to a menu navigated with the controller. The path to a specific move might look like a combo to you. Players could be given ample time to complete a turn or pressured to decide quickly - this way, it could be played either as an evolution of chess or of speed chess, the latter of which you might find to be more typical of a "fighter."
He did it in a week. Chill. I'd like to see him spend another week on it.