(Sorry for my bad english!)
for some locations often is useless to undelete and users do not search for files in that locations.
e.g.: %appdata%\(...)temporary internet files
or %systemdrive%\%temp%
or %systemdrive%\%tmp%
and so on...
It would be great for the user to edit a list of path for exclusion.
Then when start scanning, a thick selection "use exclusions" (yes/no) ...
in the list, recuva can guide/help user with the typical paths useless to undeletion