I'm of the unpopular opinion that almost all healing should be some kind of overtime healing rather than instant.
Had the same opinion in mo1. Why does all the mage healing have to be instant healing that you can only counter with other magic?
Same with bandages, why does it have to give you the entire heal of the bandage after X time? Why can't it have a much longer duration and heal a bit every now and then. With hits taken decreasing the heal also with a very brief application of the bandage requiring you to stand still. Sort of the same as it would be casting a healing spell.
Mo1 had the issue that multiple mages could work one player = massive burst heals or corruption immunity while getting healed. Combine that with a tanky player and its just way too strong and encourages the wrong kind of gameplay.(IMO)
Heals could be heal over times almost exclusively, or delayed heals (sort of like bandages but applied from range). Imagine the lesser heal of ecumenical was a X amount of time from cast on target delayed heal (which opens it up for active counter with damage or corruption). While the greater heal is a heal over time that gets decreased from hits taken, this includes parried hits. Maybe make that one of the benefits of shields, decreasing the heal reduce of hits taken when you block with a shield. Since they do little more than protect your weapon durability atm anyway.
This limits the exponential heal increase you get from having multiple mages healing one person as well as the counter healing protection that a purify coordinated mage have on top of having other mages healing. If the delayed heal time is long enough and visually apparent enough, the corruption spell could just become a complete "PURGE" kind of ability. Heck purify and corruption could be combined into one spell(for purpose anyway). They remove buffs AND debuffs. Meaning if you have some sort of damage over time effect from say, a new spell or say, fireball keeps its long range and low damage but has a tiny long lasting dot effect on it, would open up Purify/corruption's use defensively, while it can be used offensively to cancel bandages, incoming heals, heal over times, spell reflects and whatever buffs you can activate from your clade.
Mo1 overdid the staying in combat while taking loads of damage as well as the run away and getting back into combat way too quick.
But that is just my opinion on healing anyway.