I bounced around a lot on the concept because it's a tricky one and I do not have access to the best environment to experiment with it which is a prototyping build. If I were on the clock and able to test it in engine, I'd probably have a more concrete example of what I envision, which is all just to say that I haven't solidified any specific iteration of the concept as of yet. However, here are some more specifics to the general idea I have in mind and why I think it does work:
If it's on the GCD, then Drawing and Playing a card do not require being weaved onto target party members while maintaining Malefic uptime on the boss. I also would have you able to Draw and Hold multiple cards and play them in that order, so you can Draw 3 cards and begin planning who they belong on. Another idea is that all cards are played on yourself to a maximum, and Celestial Opposition is another GCD action that applies the effects of all your cards to the party. Celestial Intersection could be another GCD in this example that doubles the effect of the cards on one party member that you can use after each Celestial Opposition. This combo would also mitigate the amount of needed single target weaving. Sleeve Draw returns giving you 3 cards with a priority system... something like Balance > Arrow > Spear > Bole > Ewer > Spire, or whatever depending on what card effects I stuck to, essentially ensuring you have the optimal trio for buff windows while making decision-based gameplay about the time between those windows.
Additionally, Minor Arcana would also be a GCD card action, and would generate the lord, lady, and knave which would replace actions on your hotbar as upgraded versions of those actions which also net you those passive DPS stars. Lord replaces Gravity, for example, while Lady replaces Helios. I've gone back and forth on what I'd see of the Knave, but there would no longer be RNG with the Minor Arcana since you get all of them each time.
The DPS library would end up looking like something to this effect:
- Malefic, your filler
- A new spell that generates stars for your passive damage, replaces Combust (20 second cooldown on the GCD with 2 charges)
- Gravity, under certain conditions applies a 5% damage mitigation debuff. The Potency would be increased to match Malefic's with 50% dropoff, but costs MP. Not entirely sold on how to trigger this at the moment.
- Premonition, standard step sized AoE cooldown that puts a debuff on enemies that deals Malefic potency to them when you cast Celestial Opposition, or something similar to that.
But all of this is just one take on the idea. There are countless ways you could interpret the concept of a healer who disguises their DPS as support, and I firmly believe that's a niche AST should fill, both because it's a design niche that none of the other healers have ever filled and offers a starkly different playstyle which is a good thing, and also because, while I disagree on principle with players who have actively fought against DPS on the healer role, I do sympathize with players who do not like DPSing for 80%-100% of their GCD, regardless of whether that's 1 button, or a full rotation, and believe they deserve a healer that appeals to their fantasy. It is something that can be achieved, and while harder to conceptualize, is worth the effort.