Wow, what a game! :D
Holy shit man, this game is pretty dam intense. The graphics are the best I've seen in a flash game, so congratz. It's pretty difficult at the beginning, but once you how to work the upgrading system, it'll be a breeze.
If you ever decide to make a sequel, which you should (cuz that would be awsome), you should just replace the gas alien/orb thingys with space ships(not saying I dont like the aliens.). That would be dam sweet. Also, maybe add a few planets here and there around in the background or something. And maybe add more things to upgrade, like adding more guns to your ship.. but those are just some suggestions.
Anyways, this is a must play game. 10/10! and a spot in my favs. I'm glad that this game got featured on the front page, because it deserves it! Good job! :D