Because that's about the only big-scale war with lots of jedi in the movies.
So you want a jedi that is uber powerful? It's like getting spawnkilled by a vehicle but worse if you're pushed down etc.
or the jedi it's just like jedi academy pushing down stormtroopers. It wouldn't make a good game and don't forget the mantra of SWBF: you are a grunt.
-"The glass is neither half-full nor half-empty: it's twice as big as it needs to be."