Perhaps I'm missing the objective..
Discussion
I guess a question of efficiency. Having things pre-installed makes sense if I only need them briefly and a large portion of my costs are setup & teardown. Perhaps what your making here is a framework for people to make their custom pre-installed environment...
There's a spectrum of applications that need compute
[specific]| -----------|[fully custom]
example of specific: convert png -> jpg, one-off task
example of custom: running a webserver with self-developed software, long running
I think this solution serves the middleground, where someone needs some software pre-installed and ready-to-go but needs it only briefly for a self-defined task. GitHub actions being one such use-case.
Sounds like it's going to be a really useful framework 😀