When I cinch him up he moves around a lot, sometimes into me which I do not like at all. He will sometimes hop up a little in the front, not quite a rear but more of a crow hop. I agree that a few nips wouldn't be something worth dealing with, but I feel like the horse is a little too dangerous like this in order to not try to fix it.
I will try going slow with him, I may try using the surcingle, going a little at a time and lunging him out before tightening it again. Then repeating this process until he is more comfortable with being cinched up. Does this sound like it may work?
I will also try the other things many of you have mentioned.