NEW HEALER CLASS IDEA!

[Archwizard]

They would have a defensive CD that's a Slow.

So, on the one hand I will grant that a Slow effect isn't out of the question, particularly as Scholar previously had one on Shadowflare before its disappearance.

On the other hand, that would make a terrible defensive CD for multiple reasons. For starters, Shadowflare was AoE but only had 5% potency to balance it, so for it to be worth a CD as a defensive tool it would need to be either an AoE with low potency, or high potency and strictly single-target. And if you're counting on it in emergencies, I expect you were thinking the latter.
"Okay, one target, well what about throwing it on the boss?" There we have two more problems. Logistically, the Slow wouldn't prevent the damage, it would only... slow it, so if you intend to cast it before a tankbuster or AoE (as you would for an emergency CD) you'll only buy a second or two to top your targets off before the inevitable hit; its primary value would be in reducing auto-attack damage. More importantly though, most bosses would simply resist a Slow like all other status effect, which is why most debuffs thrown out are intended to increase the target's vulnerability to damage rather than attempt to alter their own. It's far more useful for a crowd of regular mobs who won't resist it and output more attacks worth slowing, which then makes it something of a waste of a CD.

A Blink ability with the theme the Time Mage stopped time to move to the new spot.

On the other hand... why would a healer want that?

Don't get me wrong, I understand the value of a mobility tool in a broad, general sense, particularly for casters -- but you'll find such tools beyond Sprint are more the rarity among casters, since our range tends to eliminate such needs.
BLM has two because its substantial cast times and emphasis on pumping out damage in lieu of utility means it's in the most danger during Bullet Hell phases without one and suffers the greatest performance loss on the move. RDM has two because its standard rotation features a melee phase, so they require a means to close the gap before the GCD and transition between the two roles. All the other casters get is access to instant spells so they can run-and-gun, or at the very least can slide-cast with spells they can pump out faster than the GCD.
So unless we call it a filler tool that comes in place of a healing, damage, or raid utility advancement so you have a second sprint, the only way it could directly benefit the healer's own kit is if they have substantial cast times like BLM, or lack range with certain spells like RDM, either of which would make it bottom tier regardless of how its theoretical healing/damage compares since they would affect a healer's ability to respond.

As for everything else you mentioned... AST could do that easily, and as TankHunter and Seraphor have both pointed out, already has in the past.