uhmm...
well, this game gets too hard after a time. i only reached score 7852 or something like that. Then the asteroid swarms grew over 20 and crashed through my rocket lines like nothing. If half you ships are destroyed within a minute its time to give up. my idea is to build a big circle of the bostons as high hp guard, stopping the asteroids. they are made to block, thats what i found out. Then another cirle of healers in the guard circle. They heal up the guards fast enough and it could go on. to bad my money came to slow to build at least a half ring :( game whould be better with some upgrades or new ships, maybe a 300hp destroyer for 200 coins or something like that.