There are six holes in my Atma collection that could use some quantification:
* Atma of Nightmares - Dyna Tav win -
Haste and Absorb duration (should just take two casts)
* Atma of the Bushin - Maat's Cap - HP/MP (it may not be a percentage boost to outside Abyssea HP, but it probably is. Do without Cruor buffs.)
* Atma of Hell's Guardian - PW -
Zanshin (use a low Acc/base damage weapon. Don't get STR/DEX/etc buffs and just afk on one monster with Regen Atma on) and
Demon Killer (would require BST AF3+1/2 body).
* Atma of Luminous Wings - AV -
Enmity -, and
Physical Absorb (Kparser doesn't pick it up, but if someone sent me log files I have already written a script for it)
* Atma of Camaraderie - Sandy WotG quest line -
STP, Cure Cast Time,
Song Recast Delay
* Atma of the Truthseeker - Bastok WotG quest line - DEX, Darkness resistance
Most of these Atma are easy to test, and I've linked similar tests where applicable.