I don't really like the shield transfer aspect, I think it should use your weapon power just like a normal laser with a large fall-off in efficiency. And while it is harmless to you (the healer) the target is still being fired upon by a beam of energy, it should cause heat damage while bolstering the shields. Maybe limit it to one "healer" per "patient" to avoid creating an invulnerable killing machine. Having the beams from two different healers at the same time would bork your shield modulation and stall the shield regen effects while still leaving your systems to absorb the heat of two beams, doublt heat damage and no shield healing.
I think there are plenty of way to make this fit as a logical weapon at also limit it to "acceptable" power.
I think there are plenty of way to make this fit as a logical weapon at also limit it to "acceptable" power.