I’ve got a bunch of suggestions for granular selections…
Dim out invalid options in the context menu for granular selections
It looks like I can randomize instrument or humanize effect number, but alas, I cannot! You tease me so! 
Transpose -> General purpose step down/up
Currently, transpose will still act on note data even if you make a granular selection just on instrument number, volume, etc.
What about if, instead, these become “step down / up”? Then, a non-granular selection still acts on notes only, but a granular selection decreases / increases the selected value by 1.
Randomize and humanize to work with instrument column
I’ve done this sort of thing with samples, and it makes for a fine and organic variation in sound. Being able to multiply the instrumental randomness across one more axis would be pretty sweet.
Internally, this could be done by scaling the range of values down to the number of instruments filled, then remapped back onto the actual instrument numbers. e.g. randomize on the instrument column in a song with instruments [00, 01, 02, 08, 09] would work internally by getting a random integer between 0-4, then mapping those indices back to instrument numbers i.e. 0 -> 00, 1 -> 01, 2 -> 02, 3 -> 08, 4 -> 09.
Quantize to apply only inside granular selection
Say you wanted a stepped volume change. The easiest way to do it would be to ramp the volume using interpolate, then quantize the volume column (in time).
Alright enough from me, I’m obviously getting a bit excited B)