We did cross post on #10/11.
Yeah - it's all just throwing ideas. All 6 displayed could / might be better and does fully represent all the elements.
Split Keys - was me picking up on your post #2 - acompaniment keys
Half and Half - let's make a green block which has 'equal value' to the blue block :)
I was just thinking the that 6 color blocks on the existing small ribbon might be a bit 'busy'.
So as you say - make it bigger.