I find the colour sheme a bit blah, but it's ok. I think it would be useful though that instead of the having the buttons and knobs show levels in white against Dark Blue, have each element show a colour against dark blue.
Element 1 - Light Blue
Element 2 - green
Element 3 - yellow
Element 4 - orange
Element 5 - red
Element 6 - Purple
All Elements - White
 
This could carry over to the Modulation Matrix, so it would be easy to see what Elements are being routed to to different controllers.
 
Also when jumping between elements help prevent editing the wrong ones
 
EDIT:I'm putting this image in the first post, but please see the 3rd post for details why it looks a little different

 

I like the idea of user-configurable colors for display elements.

So in this thread Shellstax and I were discussing implementing a way of viewing the Keyboard range of each element, so when you are playing you know what keys to play. You may set up split keyboard with bass sounds lower in the keyboard and accompanying sounds in higher ranges, or it may just be a patch uses multisamles and wav tables and there ranges extend differently form others (meaning some of the layers don play on certain keys).
http://forum.cakewalk.com...-m3221407.aspx#3221439
 
Shellstax took my idea of colour implimentation and toned it down so it didn't result in a tangy experience. I like it, it takes the coldness form the current set up, makes visualising what's happening intuitive, and freshens it up nicely. It's just on the one screen, but helps visualise what I was expressing a bit more

 
You'll see the this 'Instrument' Screen (GUi) is now a little larger, it's size matches the Browers (Whereas Mixer and options are both the same size and bigger). But this could simply result in the Browser being a little bigger, which is being called for in this thread.
 
http://forum.cakewalk.com...-columns-m3214042.aspx
 
 

Brilliant!! I love the idea of showing keymaps for each element above the controller ribbon.
 
As  for use in the vector mixer, I think the colors would work best it they were fully saturated and pure. Think of color picker wheels from other apps.