Hey, it could be worse...
In all seriousness though, I do get the frustration. I play on controller, and main SCH, and it is nothing short of playing Chopin's Op 28 No. 15 as nearly all abilities are consistently utilized. WHM is right on its heels with the demand, as not having a pet reduces the hotbars by 1.
I'm not going to tell you to "get better". I'm just chiming in to mention that I understand how advanced the UI and controls are. So much so that not only must you be practical, but you have to keep playing to maintain your skill level with the UI, and also get better with it. Try not to edit your hotbar/hotkeys too much, and let muscle memory take over.