I like the visuals and sounds, as these are really retro.

From a gameplay perspective I did not see the challenge. The game gets more and more easier at the end and guns are overpowered. So I did not miss any of the enemies at all.

This was fun! My only problem with it was that I chose to upgrade the machine guns a lot and the sound effect really got on my nerves. I would recommend changing it if you update the game.

i love the  graphics and  color palette. it looks great, easy to add more features later on. 

I found myself wishing the laser would hit all the enemies it went through, instead of just the ones near the end of the shot.  I also couldn't figure out how to do the upgrades, or use the weapon on M2?  I also found myself wishing there was a penalty for enemies escaping.

Nice idea but I couldn't work out how to do the upgrades. I won shooting down 58 enemies though!