As a personal design choice I tend more towards minimalistic designs. The less buttons one needs to navigate the better.
The forum itself here is a great example of that concept, it's use of muted colors and simple buttons makes it much easier to navigate than the standard everything-is-text forum format.
As that applies to your UI, try to make it smaller unless it's an openable menu. Simple gauges for xp, health, etc and a lineup of button options. Try to reduce how much of the screen it takes up!
Conserve space, and try to keep things neat and organized.
(THAT SAID, The absolute worst thing to do with that though is to put everything into dropdown menus. Be wary! The less clicks the better.)