I would be interested in a Critique Forum too. Knowing who is willing to have their brains picked for tips would be really useful :)

Favoriting members seems like a good idea to me. If I don't want a critque on a particular image, can't I just say so when I post it?

I have never been able to figure out the star system. what makes an image one star or two or three , or even 4 instead of 5,totally confuses me. So if it's great (IMO) I give 5. If it's not, I don't give any. And I admit 5 is a knee jerk reaction. If I look at an image and my first thought is whether or not I could get way with stealing it, that image is a 5 :) 
(no I don't steal any. I just wish I could.)