Q: I'm hiring a new admin. What protection do we have for data backup in case an admin goes rogue and deletes data?
A: You can use Permissions to restrict a User to not be able to delete anything. I would also advise that you create a contract with your admin that covers data ownership and security.
Please do yourself a favor and hire an attorney to draft up a document for all new hires in order to protect yourself and your proprietary information. Trust me!