Just a minor suggestion about the CTRL 1 and CTRL 0 keys to display the image at 100% or 'fit on screen'.
From a logical viewpoint I can see that CTRL 1 makes sense for 100% and I guess that CTRL 0 in this context makes sense for 'fit on screen'.
However from a practical point of view toggling between these 2 displays is something that tends to be done quite a lot during the processing phase of the workflow. The ability to simply use one hand to CTRL 1 to show the image at 100% works very well. However when I want to go back to 'fit on screen' I have to either use 2 hands to use CTRL 0 or use my left hand to do this, which is much more difficult (I have tried it and it's very awkward). If the CTRL 0 was replaced with CTRL 2 (for example) this would mean that it would be very easy to toggle between 100% and 'fit on screen' with one hand. This would simplify the processing and make it more efficient.