You could move the party list more center. When I heal I have mine just left of my toon, you can also change the size of it and other HUD. By going to HUD settings and clicking which one you want smaller or bigger, then press down your r3 button that will change the size of it.
Also in that fight it's best to have twin on focus that way you can see when she cast db and twisters.
If you don't know how to focus target you do it by selecting target then press square go to bottom of list there will be focus target.