Here goes:

1) Smart Subcrates
It would already be enough if I could create 1 level of smart crates inside a regular crate, to avoid clutter.

2) Hide live BPM for both decks when in library view (no waveforms)
Train your ears, not your eyes :-)

3) Highlight tracks that are harmonically compatible
Either implement it similar to how Pioneer do it (highlight tracks that are compatible to the live track) or add this as a smart crate parameter ("show songs that are +/- [integer] to [Camelot Key]")

4) Do not auto-remove from Prepare list
The Prepare list is of little use to me, as I will often pre-listen to tracks from the list but not play them (yet), looking for a better fit. In SSL those tracks disappear as soon as I load them. In Itch/DJ they only disappear once they are played, so and option to remove it only if more than a third or half of the song has been played, or just leave it in the list but grey it out.

5) Ability to map the same MIDI function to more than one button
My A&H DB2 has 2 rotaries, *both* of which I would like to use to scroll the library. Currently I can only map one rotary to the scroll function, I don't see any technical reason with MIDI for imposing that limit.

I know this is a lot to ask for so I'll leave the final word to Mr. Limburgh:

"Ahh, I'm also gonna need you to go ahead and come in on Sunday, too"...