As I've mentioned before, I'm working on a metaverse client for Second Life / Open simulator type systems. The existing viewers have very cluttered interfaces. There's a menu bar at the top, with drop-down menus. Looks just like Microsoft Word from 20 years ago, which is when it was designed. There's also an info bar above the menu bar, with info such as where you are, how much money you have, and what you're allowed to do at your current location (talk, build, etc.)
At the bottom, there's a row of buttons, each of which brings up some pop-up menu. Then there are 2D game objects which appear atop the play area, non-modal dialog boxes, and the occasional modal dialog. Most people keep the “nearby avatars” and “local chat” non-modal dialog boxes open.
I'd like to have a much cleaner screen, so the system feels more immersive. But not change the interface so drastically that it loses existing users. So I'm considering making all the menus disappear much the way YouTube does. After a few seconds of menu nonuse, the menu bars disappear. YouTube has a nice trick you barely notice. There's a greyish gradient behind the bottom controls, which hints at the control area without blanking out the bottom part of the video. That's worth doing.
The trick is how to get the menus back. Yeah, push ESC. But I'd like to set things up so that when the cursor hits the top or bottom of the screen in full screen mode, the menus come back. This is a classic idea that's not used much. (https://en.wikipedia.org/wiki/Fitts's_law#Implications_for_UI_design).
How strange is that in the game UI world? Good? Too weird?
On a related note, what's current best practice for displaying text chat? The current interface is a movable, scrollable window of small type on a light grey background. If that's not turned on, it shows up scrolling atop the main screen, with insufficient contrast. Should text chat today look more cell-phone like?