Regeneration/Resurrection Spells (S&W/OD&D)

I like to have potent magical healing available in my campaign, so that players need not have to discard a beloved character just because of some unfortunate accident with a giant razor-sharp scything blade-trap of DOOOOOOOOM. However, I don't much like the idea of healing magic being so convenient that reattaching a limb is as easy as applying a band-aid. To that end, here's my idea for Regeneration and Resurrection spells:

Regenerate
Spell Level: Cleric L5
Range: Touch
Duration: variable (permanent)

This spell allows the cleric to reattach or regrow missing limbs and/or organs.

A regenerating creature must be obtained and restrained, and exactly the same damage inflicted on it as on the spell recipient*. Then the cleric creates a mystical link between the two creatures, so that the intended recipient partakes of the other creature's regeneration as it heals.

The length of time it takes to complete the spell depends on the regenerative ability of the creature being leeched off, and the amount of damage that needs to be healed. The cleric must maintain full concentration throughout the process or else all benefit is lost, and the spell must be started again from scratch.

* Note that this is likely to make the creature quite angry.

Resurrection
Spell Level: Cleric L7
Range: Touch
Duration: variable (permanent)

This spell allows the cleric and up to 1d6 others to enter a mystical trance, during which their spirits pass over into the Spirit Realm*. Once there, they can track down the spirit of someone deceased and return with it to its body. The corpse will be regenerated by the spirit's self-image once it is returned to the Material Plane, so that when the spell is complete it will be whole and entire, even if it was originally nothing but bones.

The nature of, and dangers inherent in travelling the Spirit Realm are at the discretion of the individual GM. I suggest that it not be entirely easy or straightforward; casting (or partaking in the casting) of this spell can be the basis for a whole adventure in itself. I'd also suggest that the GM should adjust the difficulty of finding the correct spirit according to how long they have been dead.

All sorts of complications come to mind: traditionally the gods of the dead have been reluctant to give up their subjects, and may require placating (or duping) to get away with the dead 'un. The spirit of the dead person may have no memory of their life on earth, and may be unwilling to go back -- in that case, they would actually have to be kidnapped. The possibilities for fun are endless!

*This could probably be handled in the same way as Astral Travel, but that would be up to the individual GM