What might be easiest would be to drive from the healer. Add an IWT/CTM to your tank rotation then you can just concentrate on healing.

But its best to be able to switch to any character to play from. I am not familiar with HKN and not sure how you would do that. I use isBoxer and usually start with one of MiRai's videos then experiment from there.
https://www.youtube.com/watch?v=1MQC...U&index=7&t=0s

Some fights easier driving from the tank, some easier driving from the healer. But you could always just drive only from the healer if HKN doesn't have the videoFX type features.