I think I gave my input in another thread on this, so I'm sorry if I ignore this for now. I simply have a different view on this.
This issue affects essentially every job with single-target abilities that affect party members. Despite that, this has so far not really been a limitation for abilities such as these to be designed (tank single target abilities in particular) But I get you, so probably a reduction in charges + moving the recast higher to 20-30 seconds each (with higher potency to make up for it) might work better.The problem with making Vercure a free OGCD is that it might not be necessarily more fun depending on how it works. With many charges, you're gonna have to be target switching quite often to use them basically on cooldown to be optimal and may even take away from what a lot of healers want to do. It's not really very fun to constantly switch from enemy target to someone on party list to heal with Vercure then quickly back to enemy without clipping GCD, especially for controller players. While it sounds great on paper and makes it an actual usable button during combat, I don't know if it would be fun. I want Clemancy to behave like this (at the cost of 50 Oath), but I worry about how RDM would need to play to use it.
I think either approach seems fine to me, but the higher recast option may be nice in line with the amount of possible ogcds.
Fun fact, this is often forgotten but FFXII Red Battlemage has AOE healing and strong single-target healing natively. Cura is an AOE spell with moderate power and Curaga is a single-target heal with a lot of power. They also have access to some limited Time Magick (Slow, Immobilize, Disable, Reflect) and Black Magic of course. And their own type was Arcane Magic, which was the dark-type spells and Ardor.I'm not a fan at all of giving RDM a medica, as even in FF1 they don't have AoE heals. RDM does have access to Nul-element spells in FF1 so Magick Barrier makes sense. You can multi-target Cure in FF3 and beyond, but I mean I find that to be more of a healer/tank feature than RDM for 14.
Of course this is just me and my opinion.
So I don't think RDM having a form of AOE healing is utterly far fetched.