True. This wishlist occurs to me, to keep in mind when looking for a solution:
1. Factoring out some code commonality would be good (modulo other wishes).
2. Users should be able to save histories without necessarily saving all the
other desktop stuff.
3. Users should be able to save other desktop stuff without necessarily saving
4. Users can save multiple desktops, which should be able to have different
saved histories. IOW, a given history variable, e.g., `file-name-history',
could have a different saved value in different desktops.