For us a continuos Backup of Exchange Logfiles would be very nice in case the complete vm was crashed with all virtual disks (Disaster Recovery). We have same problems as kubimike that removing snapshots from vm will freeze the whole vm. Also using VMWare and not using storage integration. I think wenn only a snapshot from the logfile volume is taken, then the vm would not freeze at deleting this 1 snapshot. It's only 1 Snapshot-File that must be deleted.
I also see the need for a full image-level backup periodically and would do this at night time, in our case after 10pm.