Greetings @AstroBob! I actually decided to go with three separate builds: Home Console, PC, and Sinden Lightgun. I didn't originally plan for this, but BigBox is an awesome product - and with a lot of work, I was able to create a "Home Console" build of Launchbox that's 100% portable and can be easily played on a TV like a real console. The challenge came when integrating PC games, since a lot of these can't be played from a couch and need keyboard/mouse. I found it was too disruptive when someone was using my "Home Console" setup and they came across entries for "Windows PC", but they could only play by moving from the couch to a desk with a new setup. The solution was to create a dedicated PC-build which was meant to only be used at a desk. Later my brother created his own Sinden Lightgun drive. It would take me a week to reverse-engineer his setup (to integrate it into my Home Console drive), so instead I just include his build as an additional HDD and map to it within BigBox.
My feature request would unify all of these experiences. I would be able to run my gaming PC with three HDDs - and BigBox would prompt for what experience I want to have (Console, PC, Sinden) - and then load that HDD's primary setup. My examples are probably an edge use-case and scripts seem to do the job. But I appreciate the consideration and maybe community interest will grow for this feature request.