With last changes on Cooldown Speed Rate , the bard/rogue is back again with poor AOE. The main one "Mass Destruction" id 1491134 have 3s+ cd , "octave shift" id 1491338 5s+ and "Dark rune" have a blank of approx 10s without being usable.
My suggestions are : either you reduce a little bit "Mass Destruction" or you could keep it like this but change "Inevitable Collapse" id 1491133 back to how it was, that means when it's used , it gives ennemies around a debuff for some secs that double damages from "Mass Destruction"