As rad as some of those skill ideas are, the inevitable result would be having some of those skills become a requirement to do some such other content.

"Can't join our static if you don't have PotD raise" even though it's a wholly different skillset to beat PotD than it is to beat a savage raid.

That's actually why most of the rewards in the most difficult content is purely cosmetic. It's much healthier for the game and community to do that.