I've been successfully producing kids music using BIAB for over 20 years now. And in that time I've never missed an update, finally going whole hog a few years ago with the Audiophile option. (which is really worth it, BTW)
https://www.youtube.com/channel/UCLy6-72NzYpFztbJ7jNEMkgBIAB is a simply amazing and indispensable tool. Especially of use to me have been the folky, bouncy styles. The one style that I've used the most, but which needs a major upgrade is the Rehearsal Piano which was produced by PG Music way back in 2010. The timing is a bit wonky, and the audio quality is dated and not up to par with the pristine newer styles.
I would LOVE to see a full style set of Ragtime, early jazz solo accompaniment piano in multiple styles, tempos, and feels. Think Piano for silent movies. Mister Dressup and Mr. Rogers-ish. And the cornier the better!

Thanks for reading and I hope some other users will get behind this idea to gain a little traction.
Cheers, and many thanks to PG Music for this superb program.