Only shoot the flying bugs for the first two waves. This will net you 8720 on a perfect run (which is relatively straight-forward), but give you at least 8k with all 800s. Compared to about 6k if you just shoot them in formation.
Level 3+ just shoot them fkers as fast as possible.
Shoot a flagship when it comes down to stop the regular bugs shooting you, and it gives you a few seconds of peace to maul them in formation.
Pew pew pew
