If I where you I would drag my team to some test dummies and go trough each of your toons rotations.

For my own druids I did one run where I managed everything manually as if I where a solo player, and then compared that to my castsequence.

You gearscore is WAY better than my teams and I can do some instances like UK without breaking a sweat.

And like stated above, you should have the [nochanneling] in all your cast sequences.