I like these types of games. simple controls but i usually end up just running away in a circle, while the spawning gets out of control. Like the idea of weapon upgrades too. The level design was my only issue with the game. The level does not use patterns and colors in a contrasting enough manner to show clear separation between barriers and the floor. But after getting accustomed to the layout of the level, i ran around in circles trying to make progress and that was fun.
This could workout well if you matched the power ups with the level of enemies spawning in. so crazy weapons with wider area of damage.
GOOD WORK!