It's obvious you guys have someone at least partially assigned to improving the user interface. Each update has some UI changes included with it. Note I didn't say 'improvements' because many of these changes are just that, changes. Instead of spending those precious resources on making relatively non-impactful changes, like the color of an icon that has been around for 3 years or the position of a button, how about improving some of the things that need to be improved?
1. Make lock mean locked. I'm not sure what your definition of "locked" is but being able to move bars and icons around on a "locked" interface doesn't fit mine or Webster's definition. A locked toolbar should not be able to be modified in any way.
2. Fix the hover bug. Sometimes mousing over an icon will show its description until you move your mouse. Other times, it immediately blinks off make it impossible to read. Sometimes it doesn't show up at all.
3. Make hidden frames really hidden. The frame on each toolbar which contains the buttons to move it and rotate it disappears when you "lock" the bars but it's still there. If you put your toolbars close together, the hidden section will cover the icon next to it making it impossible to click it unless you click the part not covered...which is a guess since you can't see it. Either move the hidden piece to the back or really get rid of it.
4. Make your message window able to be clicked through. The message window that appears in the top center of the screen when virtually ANYTHING happens in the game makes it impossible to click anything below it until the message disappears.
5. Compressed enhancement lists should stay compressed. Some enhancement categories have really, really long lists below them that can be compressed by hitting the "-" button next to the name. This is great for making the list more manageable. However, it's completely ineffective because the instant you make a change, the list uncompresses! If I compress an enhancement list, it should stay compressed until I expand it.
6. Speaking of locked toolbars, how about allowing us to toggle the toolbar lock with a key? That would make it easy to make a change on the fly.
7. Add a "snap" feature so that we can align toolbars easily on the screen.
Since updage 5 was the Rise of the Guilds, maybe update 6 could be the "End of the Annoyances?"