Still don't see why your "4 Healer Model" requires any of the healers be explicitly low-apm with simple and little decision-making (as opposed to just letting players get by without necessarily optimizing everything, while still having that room for further/excess carry potential for those who want it), but... this honestly makes AST look no worse a fit for that purpose than WHM. (Or likely SGE or SCH. Though, that may just be because... none of them need to thus be limited.)

Initial Concerns:
Draw and Play are now GCD actions, not oGCDs.
Does this mean it effectively requires two full GCDs to deploy a single Card, or are you adding the ability for a hotbar space to act simultaneously as a GCD (Draw) and an oGCD (Play) and/or splitting those buttons?

Note that even taking up a single GCD requires that you at least double the value of the Card just to keep up with current Malefic (which is itself nerfed to make up for Card rDPS being free/bonus). For Cards to compete with a compensatory-buffed Malefic when each Card takes two GCDs to deploy, you'd need around 5x their power.

Otherwise, this seems... fine?

Reduce the CD on Cards to something like 15 or 20 sec. Still stacks to 2.
Likewise, fine.

Delayed actions are now outright actions, like as not. So Earthly Star works like Assize.
Why would that be necessary? Was this second brain cell just too much for that niche in the 4-Healer Model?

Either remove Minor Arcana or split it into a different category of buff.
Likewise, why would this be necessary? Though, you also seem to be mixing the Major and Minor Arcana here??

I've before suggested Minor Arcana be Bole (mitigation), Ewer (MP regen), probably Arrow (movement speed)
If you want to split the Draw pile in half, with generic damage buffs in the first and situational buffs in the second, that actually sounds fine... but I'm still not sure what that would have to do with Minor Arcana (Lady and Lord), and having removed Redraw, you've removed almost all agency from its core gimmick.


Broader Concerns:
Though honestly it staying as it is is probably fine, it's just WHM doesn't have anything like this to compare it to so...
Why does making AST even the "As simple and straightforward as is possible (while still at least slightly distinguishable from comatose)" niche job in your model... demand that it be WHM?

Whatever point your test would otherwise potentially have seems removed by this circuitous logic. "WHM must be the simple job because I need a simple job because a simple job is necessary, and no other job can be the simple job because they can't be WHM enough"? There's nothing about WHM's thematic components or any other job's that demands that they be simple, nor is there any demand that simplicity can only come in the form WHM currently presents.

That would probably do the general job of making AST into something for the people that like current WHM.
If the only thing they significantly like about WHM is its low APM, rather than its aesthetic, Misery, its direct damage options, etc... Which, doesn't seem terribly likely.