It's extremely tedious to export single busses because you cannot save a specific selection as a preset, and you cannot easily deselect or select a group of busses.
 
I have a setup where all tracks are eventually routed into a sum bus. From the sum bus the signal is routed to the monitor bus which is connected to the physical output. I never export a track from the monitor bus though, but always from the sum bus, because the monitor bus contains additional settings to make up for room and hearing issues. So it would be extremely helpful if I could export a single bus with one click.