Great effort!
I hate programming in Flash. I just can't get my head around the OOP. Variables NEVER seem to hold value if I place them on different layers (UGH). With that in mind I have to give you a thumbs up. Although it's not really 3D (simple side stepping and scaling). Tried the same thing in a Battlzone remake I messed around with. I know of a better method that would allow you to get a better camera angle (a bit higher in the air) and would be (almost) real 3D. Look up Freegadgets in Game Maker. Although he uses degs instead of rads the conversion isn't hard.
I made a simple engine using his method in Flash that worked , but again (Flash pisses me off), for programming anyways.