Huh, it just clicked for me that wind Uriel is... uh, wind. So would her stacking defense buff stack with Hebe's stacking defense buff? Hebe being a wind SR with a... worse version of Cernunnos (dark SR)'s stacking def buff. (Hebe's +3% defense every 3 turns, Cernunnos's +4% defense every 2 turns)
...and continuing along that train of thought, would Hebe's stacking atk debuff stack with Caspiel's stacking atk debuff?