Potentially,  you can speed up generation and general workflow in BIAB significantly....
It took me many months to figure out why my RT generation takes longer than it should, when I compared times to my older and slower machine and also with the times that a few users shared with me. Fortunately, I made a short video and tech support was able to spot the issue. It turns out there was a small file that was made time ago, for Bandstand, so that BIAB could be in sync with that piece of software. Solution was to delete it.
I  did... my  generation/regeneration and playback speed improved by 4x (about four times faster!!!!)

Sharing solution I received which solved it for me:
"The solution is to just delete this file:
C:\bb\AsstSettings.ini

Or it might be here:
C:\bb\Data\AsstSettings.ini

The delay was a very old feature intended for people using Native Instruments BandStand. Basically, the plugin needed extra time to process patch changes at the start of playback."

See if you got this magic file installed. Hope it helps someone.