So, not much that was a surprise in the relic +2 final stats, but I was pleasantly surprised by one item: Summoner's Doublet +2. I really didn't expect it to become remotely useful. Here are the final stats:
Smn. Horn +2
DEF:23 MP+42 "Blood Pact" ability delay -5 Avatar: "Magic Atk. Bonus"+4 Perpetuation cost -3
Smn. Doublet +2:
DEF:49 MP+28 "Blood Pact" ability delay -6 Avatar: Perpetuation cost -3 Critical hit rate +6%
Smn. Bracers +2:
DEF:20 MP+42 Summoning magic skill +15 "Blood Pact" ability delay -4 Enhances avatar accuracy
Smn. Spats +2:
DEF:38 MP+35 Shortens magic recast time for elemental avatars "Blood Pact" ability delay -4 Avatar: enhances Magic Acc.
Smn. Pigaches +2:
DEF:18 MP+35 "Blood Pact" ability delay -4 Avatar: Enhances attack Critical hit rate +5%
So where I had low expectations because I knew Smn Doublet +2 wouldn't surpass AF3+2 for Blood Pacts, it looks like it may have surpassed AF3+2 for idle which is a possibility I hadn't considered. You sacrifice one perp (which may be redundant anyway if you have good equipment) for a +6% crit rate on the avatar's normal melee swings. Not a bad trade-off!
Also, the head & feet have potential for BPs, but I'm on the fence as to whether they're better than the AF3 set bonus. I'm thinking no, at least for the headpiece. I just can't see MAB+4 beating a +3% set bonus proc rate. The feet look pretty strong, and could possibly beat out the set bonus.