Actually, this sounds to be a rather awesome idea. But tell me this - what hapens if a herd of onii rush into the marine spawn, demolish th paltry turrent defenses, and spawncamp the livelong day?
Seeing as hw there's absolutely no other way for the kharaa to win other than waiting that certain amount of time.
In conlusion, this could truly lead to much laming and bloodshed unless planned to the point of utter perfection.
But for starters, how would you remedy this situation?