All my frustration and disgust for the lootbox method aside, and I will not support it, the art dead (edit: art team, I have no idea why my fingers did that) did some good work there IMO. If we could pick and choose skins, which ones would you go for? Or just generally, which ones do you like best, per mount?
Raptor: I'm not overly taken by any of these, to be honest. It's not that they are not bad, there's just nothing that stands out, and the basic raptor is the best-looking mount to begin with IMO so there's less of an urge to spruce it up. Still, I'd say I like the Coastal Spiketail best because it has the most distinctive pattern so that would be my pick and one skin I'd get.
Springer: Elonian Jackalope and Windy Spot. I don't like the springer that much though it is undeniably useful, so I'm not sure I'd actually buy either of these unless they were on sale, but both skins are definitely nice. (Two thumbs down for the Desert Lop despite its handsome jaguar pattern if the ears look in-game as they do in the preview. That's not how floppy ears work. Makes the animal/biology nerd in me cringe. )
Skimmer: My least-used mount, but overall it has the best new set of skins aside from the griffon, IMO. They are all very distinctive, and the only one I don't like much is the Oceanic Ray. My choice would likely be the Dajkah Lantern for its metallic sheen and the anglerfish lights. Most of the others are fighting hard for who'd be my second pick, so the jury is still out on that.
Jackal: My favourite mount for its utility (the raptor just about beats it in terms of looks and charm), but I don't think I'd replace the normal skin with any of the new ones. Maybe I'd go for the Polished Stone, or the Banded Mystic if I could preview dyes on it to make sure I can make it less garish, but likely only if they were on sale.
Griffon: Most of these are quite gorgeous and make it hard to pick. Highlands Harrier and Clouded Corvus are tied for first, followed by Spotted Sylph and Badlands Stalker. I'd get the first two, and the other two maybe on a sale. (Actually, scratch that. I somehow missed the Corvus' stunted tail. Why do that to the poor thing, when it's otherwise perfect? )
(Can we really not preview dyes on mount skins? That's a oversight and a half.)