I'd rather just use the trait system to upgrade Cure 1 into Cure 2 and free up hotbar spaces for more interesting things. Consider older FF games. Once you get Curaga, you're almost NEVER going to press Cure or Cura again. The opportunity cost of 'they both take one turn to cast', like the GCD here, means you might as well do the stronger one, even if it overheals, rather than the weaker one, if there's even a slight chance that you don't reach 100% off of it. And if you WOULD reach 100% off of the Cura, you'd rather just do something else with the turn, then use the Curaga in 2 turns time when there's more missing HP to heal.

So with that in mind, I'd just do this:
Cure 1 is 500p, at 30 it becomes Cure 2 with exact same stats (MP cost, cast/recast, etc) but is now 700p, at 85 it goes up to 800p because of the trait you get there
Medica 1 is 300p, at 50 it becomes Medica 2 with exact same stats, but instead of boosting the potency, it attaches the HOT effect to the original Medica1. This means going from 300p, to 300p+150 per tick. At 84 it becomes 400+150pertick

At this point, Medica 1 is pointless. It's equal to Medica 2, as long as M2 has ONE TICK go out. By merging the two, it also gives more room for something to be done to incentivize using Cure 3 as your 'pump HPS even if it costs me damage' skill. ATM it's kinda not used so much, partially because Lilies can keep up with a lot of things, and partially because of the obscene MP requirement. I'd suggest something like 'when the Medica 2 HOT is on the WHM, Cure3's MP cost is reduced by 50%' to incentivize letting the HOT do it's work instead of the whole 'spam Medica' we see from newbobs sometimes.

And also do the same for other healers, like upgrade Physick into Adlo, Benefic 1 into 2, Helios into Asp. Helios, etc. SGE is ok-ish because it's got Eukrasia to help with it's hotbar realestate