Coming from someone who plays with a small group of friends, sometimes only 2 of us, I have to say the enemy count is a bit ridiculous. Might work better on servers with 5+ people but for small groups it is not really a great experience getting swarmed by enemies with nothing but a slow pipe melee.
Even a bit later on map po_merged03_2 you spawn in a small tunnel, walk around the corner just to be met with a small army of alien grunts that then proceed to spam hornets down said tunnel. The sound of combat then alerts the other alien grunts and alien slaves in the area calling them to the tunnel too. I counted 16 Alien grunts, 7 alien slaves, a couple houndeyes and a bullsquid all blocking the tunnel against 2 of us with no HEV suits on survival. Im all for a bit of a challenge but the enemy count really soured the experience for my friends, especially trying to play survival mode.
Edit: After editing the map skl files and setting monster hp values back to their defaults it made things much more manageable. 200 hp Alien Grunt + Slaves and 180 HP houndeyes might have been the issue
