I can apreciat how hard that is!
how long did it take you to do that!
few things you need to work on, mainly see if you can get the code to be more efficant, so it runs a bit more smoother.
It my help if you dont you use bit map sprites, i think flash can run faster if you dont use them.
as for the controls, they seem fairly good, would be nive if you can use the mouse, but i know you cant keep the mosue in the flash can you, may be if you have the mosue for fine aiming. the up/dwon for forward backward, and the left right for strafe. maybe even the wasd keys.