In anticipation of the eventual implementation of VNAV for both ascent and descent, I believe it would be useful to be able to set airspeed for a given altitude. Though not intended as some way to circumvent the violations for overspeeding, it would remove what can be quite an encumbrance, particularly if you’re being directed around a busy airspace
Particularly for VA event flights where there are several pilots in a long line, it can be difficult to maintain spacing. Same goes for busy approaches; most of us follow a fairly standard procedure for velocities as they relate to altitudes in the most critical phases of flight. It would be far more straightforward to set all of that up in advance.
This could even be integrated into SIDs and STARs, perhaps?