Ive always used the feature(?) allowing you to mount parts of the fs read-write persistent on the local disk which might help the sqlite issue, though not sure if thats a read/write issue or something else.
Have never used scsi for this. i suspect it's faster?
Had great experience using PXE to boot HPC farms, mounting the OS from a NAS and using only a local disk in the machine for tmp and other writable locations. I am not sure how 'diskless' linux works these days on rocky flavours but was solid in centos 5 through 7.
https://www.cbc.ca/news/canada/nova-scotia/ontario-nova-scot...