Somewhat related is this ... One thing I started doing recently is making lists that involve using Registrations (that are for specific songs), for OTHER songs. I have been able to add hundreds more songs to my "ready-to-play-in-an-instant" repertoire by noting on that song sheet (its PDF file), that the Registration for "such-n-such other song", will work for this song.

For example, let's say I have maybe ~40 Ballads that use one of the many "8beat Ballad" type styles. I have Registrations for each of these ~40 songs. But I know (or have music/charts for) another ~30 Ballads let's say. I make a note at the top of the page for each the "30 more ballads", saying, effectively "Use Registration from such-n-such other song; it works for this song too".

I then did this for LAtins (Bossa/Rhumba), 6/8 tunes, marches, rock'n'roll tunes, pop/disco tunes, show tunes, on and on. Lots of songs are similar enough to others, that you can "share" a Registration for use on several songs. For each category, I have say ~25-40 Registrations, so even re-using them, I give the audience plenty of variety in sound/style etc.

I have done this for about 300 songs so far, so that I have ~300 more songs ready-to-play, without having to make 300 more registrations. It's not a perfect system, but it was a quick way to have hundreds more songs "Ready to play" w/o having to do any more Registration work.

I even added MIDI data to each such song, so that it automatically calls up the "alternate" Registration for me, so I'm ready to play as soon as I load up that song on my iPad (using unrealBook in my case). It just calls up the "alternative" Registration I chose before, and re-sets the Tempo via MIDI if needed, then I'm ready to play.

-Jim
If anyone wants an example of this, I could send you an XLS (Excel) file where I organized some of this, to give an idea of how I "re-use" Registrations for alternative songs.

-Jim