The way we've got around it in our group is by saying that magical healing is possible but is not instantanious and is very painful to the person being healed.
I've done similar things, even to RM "instant" herbs. If you took a dose of an herbal formula that normally would restore
X in, say, 3 days, and it had been
magically altered to make the effect instantaneous... well sure, it works
exactly as advertised. And it uses a fair chunk of
3 days worth of the body's resources, and generates a fair chunk of
3 days worth of the body's wastes.
Instantly.Make sure you're somewhere appropriate, cos you're gonna want to go to the bathroom
really bad. Probably be good to have clean clothes to change into.
It could be that the healer is transferring energy and proteins from his own body (*Snigger* ) to fuel the healing.
One of the few things I miss about RM is the possibilities inherent in the transferring Healer. But yes, it should have its cost.
For that matter, back more to the original subject of the thread, I like tweaking HARP so that magic is a little bit more difficult to control and much more dangerous if you fail. I have seriously considered introducing something like sanity checks into HARP magic in my setting.
If you removed the minor healing from universal and the cantrip version only the Clerical version remains. That would limit access and make the skills Craft Apothecary, Healing and perhaps even horticulture more attractive. Dont forget rituals and alchemy too. Perhaps even the clerical version doesnt exist. Then if you break your leg you are down for a long time or perhaps need a jumping spider leg (leg), lizard tail(regen), and pure sand(time). Just healing after a big epic fight is a source for adventure. Some might find it tedious but for others it would be their cup of tea.
I gotta say it, I just gotta...
Fillet of a fenny snake,
In the cauldron boil and bake;
Eye of newt and toe of frog,
Wool of bat and tongue of dog.
Adder’s fork and blind-worm’s sting,
Lizard’s leg and owlet’s wing.
For a charm of powerful trouble,
Like a hell-broth boil and bubble.
I'm still considering what I want to do with magical healing in my game. My problem with it as written is that it's too bland, every wound should be studded with more story hooks, so to speak. I'm not griping though, not everyone wants that with their healing, and the system is intentionally designed to be tweaked. It's easy enough to get it the way I want it.