I love these kind of threads, and generally I do think you have stuff here that would make WHM a lot more interesting. Asylum however would be the most broken move in the game, so I'm not too sure about the 1hp part. Even with a 30m CD making it usable once per fight, it'd still be way too OP.

Riptide is a very interesting move. Personally I would like that in the game, but I can imagine more healers would use it to a detrimental effect rather than what you've designed it for. Plenary seems like a great change, but you need something for Medica and Cure III. I say Cure III because I think it would be better for that to not generate Lillies and to allow Stone or Aero spells generate them.

I'll echo that I don't think WHM needs any buffs right now, but actually these changes seem more like something to make the job even more fun.