Nice solution so far. Better than some of the currently available commercial solutions.
A few things I would like to see.
Have an option to password protect the endpoint client and be able to create users with limited permissions like a restore only user. I don't want end users getting in and messing with the settings or restoring files they shouldn't be.
We use endpoint with enterprise B&R server so it would be nice to be able to seed load backup data for offsite replication or be able to move backup sets to different storage. Currently you cannot do this, it ignores the copied data and just creates a new backup set.
The ability to have multiple jobs with different volumes specified to backup. I know you can run multiple jobs using the command line, but you can't specify which volumes to backup.
As some have mentioned before, I think endpoint should be developed into a commercial solution with similar features as backup jobs for virtual machines. I would be willing to pay for this rather than have to maintain two backup solutions.