Maybe re-generate selected bars only.
Maybe more tracks.
Maybe Count-In based on actual time-signature of first bar (and Song Settings Count-in) (and RealDrums Count-in Vol adjust).
Maybe a VST to sync the main Biab app to your DAW.
Maybe chord/scale note colors in Piano roll.
Maybe use keyboard styles .sty .prs etc..
Maybe midi chord track for Virtual Instruments and drag export with chord name markers.
Maybe 24Bit Audiophile version option.

So what are you hoping for ?