Hey,
I think it's quite a nice map, but there are some problems. First of all, be sure to mark all none neccesary tiles as detail, so that with high details switched of, the player is only able to see the backgroud and the gamelayer tiles (collision tiles). Secondly, some of the tunnels are just too small, especially in the upper right corner, this destroys the good movement, as it slows you down. Thirdly, I think the backgroud is too saturated in the top, but that is just my opinion, and another thing, I personally don't like is having weapons fly around in the middle of the air. (In this case the laser in the middle of the map). Oh and before I forget, sometimes it looks good to use bottom tiles in the ceiling, but i don't think it fits here, and it only confuses the player . Other wise I think the movement is quite ok, I have not been able to play the map with others, so right now I am not able to tell anything about balancing.