Those holes in his face may be normal. The first conclusion I jumped to was hexamita, but that disease rarely affects bettas and looks a lot more disgusting than clean little pinholes.
It's odd that he's still eating and isn't clamped, though. I'm really torn as to whether he's actually sick, because some of your photos of him look like natural iridescence and some look like velvet (not your fault at all, velvet is hard to spot), and I've never had a fish infected with it. Here are two very clear photos of bettas who most definitely have velvet for you to compare with: