I like that idea.

Swapping custom ROMs are the distro hopping of Android.

What I do to make the process faster is:

• Backup all my shit, with Google backup (which if it works, it is way crippled) and Swift backup root.
• Download newer ROM and desired root method (KSU as of lately).
• Flash said ROM and root it.
• Grab data from Google, give root permissions to Swift Backup and complete the data retrieval sane edition.
• Rinse and repeat.

My device is EOL and most custom ROMs come decrypted by default, so I am in no need to format data, which just makes this process faster as my data remains in the same folder, but if you have a good cloud solution and nice internet speed Swift Backup can take advantage of that.

this would be... somewhat possible, you can't really boot GSI images, however the folk at BlissOS do have an android generic project that makes porting custom roms to x86 a lot easier. By porting android images to generic x86, we can serve them as temporary VMs, just like https://distrosea.com/ (I've actually been thinking about doing something like this for bliss specifically but funding says no lol).

This is contingent on roms being ported to x86 though, off the top of my head there are images floating around for

• Bliss (Obviously)
• Lineage OS,
• Vanilla AOSP,

and specific verisons of

• Project sakura (A11 iirc)
• CarbonROM A10
• Bootleggers A10
• RessurectionRemix
• Pixel Experience
• Dirty Unicorns
• Tesla

I believe there are also images of LMODroid and Calyx floating around... somewhere

You can try emulate the ROM on your phone itself like this app https://play.google.com/store/apps/details?id=com.vmos.google