A few more suggestions...
The temple walls that raise should not let you walk through so quickly, even if you crouch. This may make more sense on the classic versions. The fun was always waiting to see what was on the other side rather than making a mad dash.
The 45 degree walkways where the turrets would be housed in Egyptian could be made a bit lower so that you can step through it. The room where the sarcophagus is that contains the two double doors with the dropdown should be one-way for playability.
You should be able to walk through teammates but not enemies. In complex, people get stuck very quickly. It might also be a good idea to include indicators on people's heads if they are on your team. I know this is not the original territory of the game, but would add playability. Respawn timers are a very good idea as well, because they make it so that everyone doesn't die instantly, and they can see where the enemies are fighting.
Incorporate a fixed cam in the level with the description in white text with a black outline that all fades out. Head zoom would own, at least in the first timed spawn, but maybe the logistics would be too much.
The large screen on control could benefit from a countdown timer if the round is timed. Otherwise, it could blink 0:00. What I'm referring to is a small clock in the bottom left corner. It cannot be destroyed so this would be a nice touch.
Drivable tank (a boy can dream). Maybe you can make the existing one act like a HL2 turret. Or maybe one person could drive and the other would shoot?!
The death gif of blood should be a little more dynamic, with an added fadeout effect.
Start with a PP7.
Ok thats all for now. Great game, very addicting. I will be back for more!
