I left a comment on a set just now that I hope will be taken as it was meant, as a constructive comment. It was nearest I have ever come to saying something negative although it wasn't meant that way.
When I look at a set on SG I always want to feel like the model is enjoying herself and doing something she wants to be doing. I would be horrified to think that anyone was being coerced or felt that they had to shoot something they were uncomfortable with. My favourite sets are always the ones were the model looks like she is having fun, especially when she gets a chance to show her playful side or when a mischievous look sneaks in. Enjoyment is contagious, and can also be very sexy.