Backup management portal is difficult to manage for hardware/OS upgrades. Not all agents are supported in it either.
New product support - vSphere 6.5 is still not supported and doesn't work.
Scheduling backups are too time-consuming compared to other products.
Finding the log file from email alerts is almost impossible. Log file names on the Director are too generic and no identifier in the name.
VMware backups provide no way of centrally showing what VMs are backed up. You have to use the notes of the backup job and manually check each VM.
Overall product management is complex. Many different components that work together but there can be 3 or 4 places to check for problems.
Backup reporting is there but requires yet another component to be installed.
Deduplication only on a per job level.