I think the UI right now is pretty bad, considering all of the stuff you have to manage.
I think a better way to handle it would be to divide the actions by tabs, bonus action/action/reaction/item. Keep the movement/consistent actions on the left for everyone, but I think dividing it into these tabs (and having a button to show all possible options, since there will be so many eventually for spellcasters it will get ridiculous to put it on one tab) will make it MUCH easier to parse the information.
Right now it's really annoying to have to constantly open menus and such to drag the spell/item/whatever you need into your hotbar, when really it should just be divided into larger tabs so you can both sort the options as well as display more at a time.
