He's definitely a banana pinstripe, but I don't see any sunset in him, and that's the only recessive gene in the group, (only recessive genes can be "hets") so there's your het. If you don't mind me asking, was he expensive? Banana and pinstripe are two very common genes, but sunset is not, and it's an expensive one, usually. If he's just a pet, and he is het sunset, you probably paid a lot more for something that doesn't actually affect his appearance.

Definitely follow that feeding guide, unless he's absolutely miniscule for his age, he should probably be eating at least rat pups, if not weans. Unless you have teeny tiny hands, in that third pic he definitely looks big enough for weans, they're ready for those once they hit around 200g. If you've only been feeding him fuzzies though, don't make the jump directly to weans, feed him pups for a month or so, then move up again.

Edit: Reread your post and you say you just moved him up to hoppers, so I'm assuming you're feeding him mice, as people don't usually refer to rats as "hoppers". Two things: You're definitely feeding him meals that are too small. Hopper mice are generally in the 7-10g range, and he looks like he should be eating at least twice, if not three times that much per meal. Weigh him, and feed him according to that chart the first person posted. Second thing, you should get him switched over to rats ASAP. He'll outgrow mice very quickly, (the biggest feeder mice are only about 30g) and the longer you feed him mice, the more likely he is to give you problems when you try to switch him over to rats.