I don't know where to start (drops the list of glitches and hears a loud thud)
Button smash glitches work as well. Any talents that require setup seems to be the key. Was able to time wombo combo with livid (Think thats whats it called). But cooldown never popped, got a free one most of the time
The dragon doesn't reset Killer Set, so Zither can play a sequence of songs and hit her for stupid damage with every subsequent basic attack. Looking forward to fighting the dragon like this is half the reason I even played as Zither.
Darkspawn emissaries, including the alpha, have projectiles homed towards them. Leaping Shot = 12 guaranteed hits, a shot with Griffon/Hakkon = 3 guaranteed hits, etc.
Spamming upgraded War Cry with no enemies in range lets you stack the armor bonus infinitely (up to 9,999 armor). It'll start wearing of when the cooldown is triggered, but it's fun to be the nigh-invincible bolter magnet if you get the chance.
That's all I got...