I'll just chime in to say that I don't really feel SCH is a gimmicky healer. It was (IMO) a really well designed alternative to just straight healing. My "proof" will be that their new skills were able to integrate into existing systems (ie use aetherflow, modify how existing SCH abilities work, etc etc). Even with the relatively homogenization, SCH is very distinct from WHM.

Now let's look at AST. Reskinned WHM spells... bolted on card system that doesn't integrate with the rest of the class... Yep, that I'd call gimmicky. (I say this even though I do enjoy AST)
I'm using gimmicky to describe the extra "mechanics" that certain people are up-in-arms about WHM not having. It's not a "category" of healing skills, necessarily; please don't take it as such.

Well, lets see, you have a shield and weapon so you can both block and parry attacks, which is an active mitigation of damage.
This is no way would provide a different way to play WHM, period. WHM shouldn't be taking damage, ever; if you are, chances are it's game over anyways when it comes to group play. It still would change absolutely nothing about how WHM actually plays, and the amount of whining that comes with people having to gather two weapons to get a comparable bonus to classes that have to gather one is reason enough to not bother with considering the idea.

If your entire argument as to why WHM "doesn't have an identity" is based around the fact that One-Hand/Shield combo is no longer a thing, I'll be done from this point forward; it's a completely pointless discussion, and holds no merit on how WHM actually performs or what it's identity is.