While editing the blurs on a sequence, it would be convenient to have the left and right arrow keys allow navigation through the sequence. As it is currently designed, if you find an image in the sequence that requires no blur editing, you must roll your mouse to the navigation at the top and click on the arrow buttons. This takes time, especially if the user has a large monitor. It would be faster to scroll through with the arrow keys.
Is there a reason for the ALT modifier? It’s kind of far from the arrow keys on a full-size keyboard and IMHO not necessary. Plain arrow keys would do.