I play guitar over my own biab tracks. Pretty similar to your use case.

I use Anytune pro for my mp3 playback at gigs.
My “normal” arrangement is
Intro
Head (melody)
Improv chorus(1 or 2)
Head (restate the melody)
Outtro / ending

I set a loop inside Anytune on the improv section and take it as many times as I need/want

I alsohave a Bluetooth pedal that makes this (and a few other functions) very easy.
Leaves the hands free for playing.

biab2024(Mac) Latest Build
Mac OS Sequoia 15.0.1
Apple M2 pro 32GB Ram
Logic Pro 11