I would prefer they combine the effects or make something entirely unique for ast as it stands diurnal is almost ok
Because of its increased potency but noct is a bottom of the Barrel ability

If we went the unique route I'd still opt for aoe thrill of battle when you enter the buff and either random card effect or a new card effect on all players that enter. Keep channeling would be fine in this situation. Basically start channel and people enter for buff and can continue playing. Also a mini mp Regens as a side effect would be amazing.