Honestly, if that's how it's gonna be I probably won't join any. I thought the idea of forum members starting group build ideas was just to have everyone screw around on the same kit and see what everyone comes up with. If we need mod approval it sounds too official, like it might as well be a judged contest or something.
The last time I joined something that it completely killed my gunpla mood, like just putting together a model seemed like a chore. I'd rather not take a chance of that happening again.