I've tried reiki before losing my mind. I think that lead to my losing my mind because she said your brain energy is scrambled and I can't unwind it. A year later I broke down mentally. Never gone back.
Shaman I've gone to twice so far. I really enjoyed it, though I don't know what she actually did for me. After you mentioned soul retrieval I do recall her doing that. I just know I feel better after a session, but its far and costly don't do it often.