Damn, Mr.Late is saying everything in every thread I want to say. :/
I liked the middle and the 2nd point, the last point was just bad because of the vent + it was at an uninteresting place, might want to put some more creativity in there.
Then you could fix the sniperlines at mid and please fix the respawntimes, you should never go above 20 seconds (what your map does all the time), because that is just a too long waiting time.