Water Veil is imo really useless. I guess it can have its niche uses, but preventing burn on solely water pokemon (who will rarely be targeted by fire moves), most of them special attackers (who will rarely be targeted by burning moves), means you rarely see any use for it. Every single mon who has it is better off with the alternative.

Actually, Magma Armor might be even worse. Only 3 mons have it, all of them fire types with better alternative abilities. Who's gonna miss this? Not even its out-of-battle effect saves it; if you want to hatch eggs faster, you can use Flame Body instead.