I will add a Web.config setting that will make it possible to allow deleting from the editor file browser when using a user specific folder, so it is possible to allow this without adding the user to the delete role which would allow the file manager.
The new setting and related comments in Web.config will be:
<!-- if a user is in a role that allows both uploading and deleting then they will have access to the main file manager
in some cases you may want to allow users who can only upload to user specific folders to delete files from the editor file browser
without giving them access to the general File Manager, to do that you could set this to true
<add key="AllowDeletingFilesFromUserFolderWithoutDeleteRole" value="false" />
So you will be able to override this in user.config to make it true.