I'd like to be able to change some of the window sizes. Particularly the Chat box. For me, it is too tall, but there is a limit to how short it can be. I'd like it so that it was only a few lines tall.
Also, the current space hotbar of 8 or 10 keys is not enough. I'd like to be able to expand or decrease as I see fit (up to a reasonable amount... say 15?)
Also, it would be nice to be able to move hotkey bars vertical, and to split them out... such that I have one horizontal and one vertical for example.
If we could add skins or mods to the UI(i'm not saying advanced scripting from something like wow, but something, at least), cryptic could keep on with it's core UI designs, while those not happy with it could change it to their heart's content.