just adding a small note on this thread as it's kind of related... ( not packages but streamlining conf backups @ handling of ext4 or pure extroot systems )
sysupgrade needs some tweaks for non rom based installs... at the moment the 'help' is not specific about which features are ROM only features...
i.e.;
[root@dca632 /usbstick 43°]# sysupgrade -c -l
Cannot find '/overlay/upper/etc', required for '-c'
[root@dca632 /usbstick 43°]# sysupgrade -o -l
Cannot find '/overlay/upper/etc', required for '-c'
###### this is the only help line re: rom
# -u skip from backup files that are equal to those in /rom
might create a new thread regarding improvements to config migration etc. as above in the future...( ext4 tweaks ) if anyone else is interested, create a thread and tag me...