Indeed there is such a list. Follow this link and get the attached file in the first post.
http://www.shrapnelcommunity.com/thr...&Number=586140
Yes, a nature blessing do allow your sacred undead to pull themselves back together again, so to speak.
Nope, your Pretender can never bless itself. Picks in nature magic only strengthens an already present regeneration (or one granted by items or spells), but it doesn't grant it. There's a cheap lowlevel nature spell called Personal Regeneration though so this drawback is pretty moot.