Seems more often than not turrets are positioned strategically. But troops aside from snipers are not as they free roam and typically bunch. That is good in a lot of instances but some method in the madness would be good too.

All bases have weak spots and areas which are strong. The npc should position accordingly. Not remain static but move within an area. A base at a top of a hill surrounding by rocks faces should have a weighted defense towards the entrance, or mouth of the base. Why not have qrf in the base in small squads that appear from different buildings each time in a different number. Additional support should still be called by the radio guy. Npc groups could rotate position.

The challenge to infiltrate bases is good but please keep improving it.