http://imgur.com/coo1vUw <--Here,what my proposition is.
It's NOT pixel perfect. I don't have the assets that GGG has. Obviously. (I CAN make it pixel perfect,if GGG want to let me fiddle with it and send all the assets, or if I invest in it and create a complete new one from scratch)
It's just an idea.
Chat is no longer in the way of other windows. Its smaller,more compact and leaves a huge space for potential on other mechanics that may need visual indicators. (Also you don't need to put on every icon what it opens and what is the keybinding, mouseover indicators are just fine.)
I didn't bother on changing the Shop button,but I agree at least to be the way it is now.It's like a generic site button,really bad.
Embrace the 2014 and the fact that people have large and wide screens ( 27"+). Edge to edge UI is not really that great of an idea in this day and age, in my opinion.
And don't say it's too Diablo. It will be a tragic irony,especially on this game...