I think Garuda is so dominantly used among other avatars because of the increased Evasion and Karura Hachigane (Garuda -2perp./ATT+/DEF+).
I had the idea about splitting the bloodpact timers:
Blood Pact: Rage (recast 60 seconds) avatar uses a strong offensive bloodpact
Blood Pact: Anger (recast 30 seconds) avatar uses a medium strong offensive bloodpact
Blood Pact: Ward (recast 60 seconds) avatar uses a buff on the party
Blood Pact: Spirit (recast 15 seconds) avatar uses a healing bloodpact
Blood Pact: Animosity (recast 25 seconds) avatar uses a debuff on the monster(s)
