It would be interesting to have a healer class or another method of healing however...
Also as Dr Disaster states scarcity really does not exist unless you play hard mode and do not already know the layout well of the maps.
The issue as far as I can see in adding a new method of healing aside from camping and potions is the strategic element and push for some battles to coordinate potion quaffing strafing and foresight would be changed in proportion to however potent hat new healing method was.
I believe even at Hard mode with healing spells for example you could zerg everything.
Single healing spells would be difficult with the given mechanics because we do not choose the recipient.
So we would likely have a full party heal which could constantly be readied on our mage.
In the game healing can be done over time by just standing, crystals, potions and resting. (and since regen is by far faster than LOG1 a quick rest behind a sealed gate is full health) imo regen is far too fast .
I feel unless enemies were also given healing capabilities the overall design could be altered a lot by adding more healing methods.
I will second the fact that Alchemists dupe trait/skill is amazing. On my 3rd playthrough I had 3 of them and something like 40 stat pots.