The worrying thing with Moeroa isn't his ability, it's his concussions.
The dude will be a 300 game NRL player if his head knocks don't win the race. He's already got 100 at 23 and he's clearly a genuine first grader. I've said a few times that I think it's also quite clear he grew up as a beast of a kid who just ran over other players, and never learned to run a line like, say, Lachlan Fitzgibbon. So his junior form in hindsight was a bit misleading.
I reckon he needs to sit out a bit, for his own health and for his football too. I wouldn't be cut up if he left but I also have no issue with him staying on.