I don't think he'll leave. The impression you get is he's sussed out how good he is and what standard he can play at and is doing that using the money to help get on with the rest of his life (fatherhood, studying etc). If someone was going to come in for him full-time, they would have done so by now and I reckon he's happy here and sees no reason to go to another part-time club. Though as KoN says, anyone in this league would have him tomorrow.
As for people who criticise him, I'm always surprised that folk can watch a lot of football and understand so little about it. I don't have problems with his work rate, but even if I did there's no point running himself into the ground if he's too tired to take the chances when they come...