Absolutely fantastic map, just like all your maps - what I like about it is that they incorporate systems a couple of years ago no one would have even thought possible in wc3.
The idea is great, I noticed there is a load of weapons in the inventory - this would be ace if in the final versions you had more than one more weapon (something missing in sharpshooter online), for e.g. a shotgun.. more damage closer, and the bullets arc out, this would also help add variety as people may choose to not even scope/aim with such a gun but just get close and and blind fire, then as mentioned above a machine gun or something. Just having those 3 would add an unbelievable variety to the game without making it tedious and complicated to learn.
Things you could look at:
As nice as the auto-aim feature is.. I have to admit I found myself using it too much and found it to easy to get kills by doing so, because the aim/walk system is really hard to get used to.
People have mentioned combat zone - I to believe this uses WASD to move, which would feel a lot more natural (then use the arrow keys to aim/look around) and would considerably flatten the learning curve and perhaps fix the above to a degree.
Other than that this is ace and has unthinkable potential, finish it!
EDIT: I apologise, I tested it and combat zone doesn't use WASD but the arrows keys... sorry =(