excellent potential!
Firstly, it ran fine in IE for me.
For first time players, do not forget to buy upgrades. I did, and it gets immediately easier after you do buy them.
Suggestions:
-add lives
-add shield, and upgrades for it
-add some kind of special weapon to use in a tight squeeze, maybe a few special weapons based on different play styles
-add levels, and put the shop between levels
-more enemy diversity
This game has incredible potential. Everything looks great, but the gameplay is dull. With the above upgrades, and some levels, this game will be good enough to make it into my favourites. Right now it's just too dull. If you're willing to put a bit more work into it, PM me and I can give you more detailed suggestions, and I don't even want anything from you but a good game to play.