I'll be honest, I'm not a fan of adding more or fewer heals at a sanctuary. Especially since I don't see this being particularly prevalent anyways, you could always just have the line, "At the start of the fellowship phase, heal a companion if at a sanctuary" on the, I don't know, three companions this would apply to.
I'm just not a huge fan of adding a ton of healing to the game, especially if it is semi-permanent.
-wtk