Maps should come in a variety featuring Jungles, Deserts and Swamps, there should also be a forge in this game, where you can actually pick up Fire-Arms instead of swapping when you're about to respawn
Second boss is easy, wait for his weapon to be tossed and deflect it with the shield and his weapon will stun him for a few moments, long enough for you to attack him.
When you get the flamethrower, move the mouse in a circle around the character. It's an easier way of surviving without waiting for gun clips to reload.
Useful tip: When you're up against a boss, fly up to either side where the saws come out, but you have to time this correctly, once your on that part, jump on his head and shoot down on him, but you have to keep jumping on his head or you'll fall off and lose some major health.