Nice job.
Yup, I liked it. ...I dunno if you can toggle between mouse and arrow keys, but I would have preferred the default to be the arrow keys and CTRL or SPACE or something... The weapon status icons, the enemies, the scenery, ...everything looked profesionally done, but the repatitiveness got the best of me by level 5. I didn't feel as if I accomplished much after completing a lvl... There should have been a little intermission or something where you watch your points rack up, maybe buy some better armor or something.
Maybe also pay more attention to flight paths? ...like, the jets and planes looked like they were floating around in space. Maybe you could add some 'turn left, turn right, dive' animations? That would add soo much more to the game... ...in more ways than one. lol
Just some of my thoughts. Thanks for the game, man!