I don't have a critique, but I think he's really cute! I love cremellos! As for what it is, it's basically a double palomino.
And as for the sunburn thing, I think it's an individual horse thing, the one we had never sunburned or had any issue because of her color. At first I just assumed it was a myth, but I have seen pics of other cremellos that would squint in the sun like it bothered their eyes (your's isn't squinting in the summer pics, so it may not be a problem for him).
Then I've also had people tell me they sold their paint(s) because they'd burn so bad on their bodies they couldn't ride them, I've never had a horse (of any color) burn anywhere but their faces (and it can be just as bad w/ a large blaze). If he does have a blaze it may need sunscrean, but otherwise I'd wait and see if the sun is an issue for him.