I use BiaB to:

A-the MIDI side
1-input different chord progressions to see how they sound in original songs
2-play with styles for original songs
3-drag and drop the above 1+2 into my DAW
4-practicing soloing my guitar or wind controller
5-practice my sight-reading. I will randomly pick a song from a fake book, load the appropriate Norton fake disc, then sight read with either my guitar or wind controller. BiaB, a fake book, and the companion Norton fake disc are a natural combination.
6-try to duplicate problems to help others
7-to make backing tracks to help my students
8-to print out either chord or lead sheets
9-when in a writers block I will use the melodist or soloist for inspiration

B-the RealTrack side
1-to create backing tracks for some of my jams and/or songs
2-to create backing tracks for others, including students
3-to add a track or two for my MIDI songs

I do not use the VSTi version of BiaB.
It has been a joy being quarantined with my wife. We've caught up on all the things I have done wrong in our 53 years of marriage!

64 bit Win 10 Pro, the latest BiaB and RB, Roland Octa-Capture audio interface, a ton of software and some hardware.