You don't need to place him in a separate tub for feeding. It will most likely just stress him out. It's perfectly ok to feed inside the enclosure. Don't worry about making the hides smaller unless you can't get him eating. He'll be fine in slightly larger hides. Sounds like he's just busy being a snake, nothing to worry about.

You could consider making his warm and cool end hides identical so he'll choose the right temperature over his favorite hide. However, spending time on the warm side is perfectly fine. He'll go where he wants, and as long as the temperatures are being measured correctly, he's in no danger from spending time on the warm side. Some of mine seem to prefer the warm side as well. They know what they need better than we do.

Just curious, but what morph is he? He's stunning. Oh, and do you have a picture of your setup?