3 issues: Needs hotkeys. When you purchase upgrades one at a time, it uses more points than if you go straight to the max you can buy. In the later levels, when it says how many tanks coming in the next wave, it always says 20, but much, much more than 20 attack.
Fun, but the Poseiden's Blessing upgrade doesn't work. At least sometimes. Occasionally I'll be able to fly through aircraft with no problems over water, but most of the time I'll end up with a game over screen when I get surrounded.
For those that complain about the nightmare... Reading the codex is helpful at times. Just sayin'. Just like instructions in real life. It saves time and frustration.
So if you die on any boss, he and everything else explodes, so that may be what everyone is experiencing when they "kill the boss and die right after" and not win. You just died. You didn't kill the boss.
Well, as I write this comment, I managed to get the ball in a perfect orbit so it won't hit any planet for a long time. Oh, wait, there it goes. Wow, that was a long time.