I would find it useful if Dropbox offered the option to require a password whenever the user changes which folders are selected/unselected in Selective Sync.
Example problem...
Computer A: my personal PC used exclusively by me - all Dropbox synced
Computer B: shared device used by me and co-workers - only one "work" Dropbox folder synced
Problem: Co-workers using computer B can change the sync settings to access all folders on computer A (not good!)
Solution: Allow password to be enabled when changing Selective Sync settings
Thanks for reading!