Yeah... the boss battles are not the games strong point. I ignored them and just powered through them with gunfire rather than strategy. I just dodged a little and stayed firing. The first boss pisses me off. Not fun, but it lets you continue. I spend a lot of time exploring actually. The characters only respawn a certain number of times also... then the level is "cleared" and you can go back to at least some points. Sometimes the backtracking path is blocked.
MrBlackCat