Most people on this board will recommend feeding them inside their enclosures, myself included. It will not make them aggressive and you'll probably get better feeding results if you feed them where they're most comfortable.
He could be favoring the cold side because he feels more secure in whatever hide is on that side. I would recommend getting two identical hides so he is more inclined to thermoregulate. Also make sure your temps arn't hotter than what you think on the hot side: if it's too hot that could be another reason why he's not going over there. If your UTH regulated and how are you measuring temps?