Is Vishnu not considered in a burst team or something?

Sure if she gets whacked, her stacks vanish (hence why she has 2 turns of damage cut and eventually gets rebalanaced to get barrier upon burst)...

But she generates no less than 30 burst a turn considering her buffs have 1 turn cooldown and stack... so assuming you use all 3 skills and get triple with her, that's 60 on a turn and she can easily get the other 40 on turn 2 if you got someone like Michael.

Is the others just better, or is vishnu's drawback that detrimental?