Really, my only UI wishes are:
When ever you click the 'action' icon
Be it Aetherite, Fishing/Mining/Botany Node, Trade Request, Party Invite ETC it takes you directly to the relevant window for that action icon.
Not open menu, only to have to select the same bloody icon again from the menu.

Being able to fully customise my own key binds.
and..
Increasing the number of rows on the skill bar from 3 to 5 would be nice too.