Try staying in the center and just focusing on the beams that come down directly above you. Avoiding just those ones simplifies things. Also playing it in Cinematic Mode (top left of game screen) helps too.
Level 1 takes all of 3 seconds to finish. The more health your guys have the more money you earn. You can easily max out stats and weapon ammo in like 5 minutes.
 "ELEPHANT RAVE"){kind=icon}
 "Gravitee Wars"){kind=icon}