Okay, so a couple of things that would improve this: 1. Endless levels. You could just have endless bubble tanks! 2. Upgradable parts. Instead of just having a crap load of guns, you could just have a couple of heavily enhanced ones. 3. Currently, the save just saves your tank. I think it should save your level-up progress. I hope you'll consider these. Please press +!
Okay, when I first played this game, it was on Armor Games. I thought it was awesome. About a year or two later, I see it on Kongregate, with badges and a boss stage. Lesson here: Kongregate makes absolutely EVERYTHING better.
 "Drillboid"){kind=icon}
 "Reckless Speed"){kind=icon}
 "DarkOrbit"){kind=icon}
 "ClickPLAY 3"){kind=icon}
 "Fantasy Online"){kind=icon}
 "Ministry of War"){kind=icon}
 "Guy of My Dreams"){kind=icon}
 "Bustabrain"){kind=icon}
 "Kongai Launch"){kind=icon}
 "Bubble Tanks 3"){kind=icon}
 "Survival Lab"){kind=icon}
 "DuckLife2: World Champion"){kind=icon}
 "Corporation Inc."){kind=icon}