You can still keep VM templates in a separate folder, working with them individually. Or you can use Content Library in vSphere 7.0 along with Check-in and Check-out. In the updated suite, you can use versioning, manage your templates, and keep track. With these new options, you can revert to the exact version from the list or just delete it.
Read the article by Vladan Seget of ESX Virtualization (vladan.fr) to see how you can manage your templates in a neat new way and make your VM routine more precise.