It's obvious that the ability to delete can do serious damage, and ability to create a directory anywhere on a server can be just as damaging. It is much easier to find data in a tightly defined user or group directory rather than search the entire server. Work towards data organization. The only accessible areas to end-users should be in the user and group data area. Prohibit saving of critical data on local hard drives.
Businesses spend lots of time, energy and money on server backup systems.
Create private user directories on the network. Give each user an area on the server that is private to save files and establish a specific drive on everyone's computer that points to their network directory. Let them know that it is only accessible to the individual and the server manager. Allow them full control to create, change, delete sub-folders within their private network directories. Create group directories.