In reading this, please keep in mind that I am a passionate newbie at best to BIAB.

It has been my very limited experience that BIAB default settings, reverb in particular, lay into a mix pretty well without doing anything else to them in BIAB.
Then, in the DAW when the entire mix is there, they may sound fine or may need some adjustments...but I believe it is better to do it in the DAW...because then you arent compounding changes upon other changes made in the original program.

Regarding exporting...Use BIAB as a plug in so that you are in the DAW when you are using it. It is a lot easier and a lot more seamless and you can ear test then and there._

Side note...
Multi riffs is my favorite BIAB function. I read that it cant be done in the standalone, but if you plug BIAB into your DAW it is available. I highly recommend learning to use it. I am personally able to get better and more natural sounding piano solos using BIAB MULTI RIFFS than I am with EZ KEYS with little effort.