Best alternatives to back up PR4100 to EX2 Ultra within internal network

From my research so for within WD’s internal options, there is either using Smartware installed on my laptop or the Backup option on the PR4100.
It appears the using the Backup option on the PR4100 only allows back ups at the Public folder level, so it’s all or nothing and I can’t exclude certain folders/subfolders.
It also appears that to use Smartware, I’d have to install it on my laptop (WIN10) to do back ups, so my laptop would have to be connected to my network and turned on.
Is this a correct appraisal of my options?
Are there better alternative within or outside of WD’s solutions?

WD Support’s response was:
"I would like to inform you that WD SmartWare can backup computer data or backup external drive data means the drive which can be connected directly to the computer and mounted as a external drive drive.

WD My Cloud PR410 is a NAS ( Network Attached Storage device ) which will mount as a Network Share on the computer. The data which you stored on your PR4100 can be access through Network Tab. Unfortunately, WD SmartWare does not have the feature to backup the network share of the computer or any other NAS drive which is connected on a same network."

From the many responses from WD Support on my questions, there is only one way to back up one NAS to the other, and that is using the Backup function on the PR4100 using the Remote Backup function, which is all or nothing type of process to back up a share.

I’m currently looking at arcbackup.com as a potential solution.

Am I the only one trying to do a NAS backup in this way?

I’m also looking at Acronis.

In retrospect, I made some asumptions that WD would have really great backup options, that is not the case. Their NAS’s have a set of backup options, but you have to read them very carefully to understand their limitations.