I'd love to see some sort of notepads in the game gui. I often tend to remember "do this today", "do not forget to this" and so on. Opening any external file is not as convenient and not server saved, so do not transfer to wherever I log on.
Also I play on widescreen often and there is bunch of unused space (mostly) at left edge. Can be like chat tab perhaps or so.
Note: maybe I can create private group with just me and post messages/notes. Ugly but can work :)