If your eyes are moving about the screen too much, I would recommend reorganizing your HUD so that everything important is all in one central location. That should solve that issue. For example, everything on my screen is centered around my hotbar—

My cross-hotbar is at the bottom of my screen directly centered (I play on controller because it’s what I’m used to, and I don’t like keyboard/mouse). Under that are my HP/MP/TP bars, and above my crossbar are (in order going up): Hotbar displaying important cooldowns so I know when important things are up (like buffs/cooldowns), Enhancements bar (blown up at 110% so I can see it and the timers better), and then the Target bar. That way I can see my DoTs on the boss, their HP bar, and my own Enhancements—Dualcast will show up there.