Also, what was everyone's tips with getting a big score in Score Attack? I assume it was nailing all of those sliver orb things to rank up a lot of points?
Do you mean the pulsating orbs that blow up everything on screen and give you a temporary shield? They just do that. Blowing up everything on screen and giving you a temporary shield. The real points are hidden beneath some round beige tiles. The more of those special tiles you find, the higher the bonus points stack up.
About the snake heads, you can get higher points by shooting at the snakes/worms
before destroying the heads. Each head spits out up to three of them.
Also, when you get to the boss, you need to shoot it down in one go -- that is, before it spreads its mechanical wings. You'll need a powerful weapon for that, two blue orbs and a yellow one (or two yellow orbs and a blue one) are the combo of choice. When the boss goes down in flames, keep shooting at it, you'll get extra points.