Mixing with 4 decks, I find the 2 x 2 layout confusing as any mixer has the channels 4 in a row.
It would be good to have a layout that arranges the decks as 4 vertical stripes to match the mixer. I think it would be possible by stacking the buttons in to more rows, and having all the mixer controls at the bottom.
Also, making the focus deck a lot more visually obvious would be great too.
I have cut a paste a screenshot to show what might be possible.
I mix externally, the screenshots I used contain mixer controls I don't need, but I have them visible just for the level meters.
I have squashed the waveforms a bit in the parallel view … it would also be good to have control over the height of these.