Here's a remaster program (GUI) for KLV-Airedale (xbps package, install and run from Menu > System > KLV Remaster).
It's using gtkdialog for the main GUI and Xdialog for some other dialogs and the progress bar (mksquashfs progress creating SFS)
Based on a concept that I earlier shared (for Weedog) but much more extended.
The (simple) concept is to make a SFS from the running system "/" and use the (advanced) mksquashfs exclude and wildcard options (no mounting or overlay involved this way) .
Everything will be merged in a single .sfs, not only the changes you made, but also the contents of the extra .sfs modules loaded at boot in the frugal install.
Read the "Help" and click the "Exclude" button to specify which files/folders you'd like to exclude (e.g. cache files or browser profile folder).
This exclude option is not the most user-friendly perhaps, but you can specify exactly what to exclude from the remaster.
If the purpose is to share the remaster with other people, you must know exactly what to exclude (e.g. don't want to share personal files or passwords stored in the browser profile)