Hi there.
It would be fantastic if you could add possibility to move START and END of the highlighted sample with mouse? I know there is CTRL+B for beginning and CTRL+E for sample selection, but think about moving these marks with mouse? You can also add possibility to move selection around with holding CTRL key?
Have you seen Wavelab? It has excellent shortcuts and realtime movement [drag & drop sample or part of the sample from one window to another; possibility to control VOLUME with vector graphics… etc.] All this is shown in realtime, Wavelab draws waves fading up or down sample graphics as you can draw & move control dots over your sample.