How about a command line file manager like midnight commander? I know there is browser based one, but its junk. I go to move a file, I scroll to the bottom of the pop up window and when I select a folder it goes back to the top and I have to scroll back down again to drill further into the folder each time.
You posted this in the wrong ideas board. This ideas board is for My Cloud & My Cloud Mirror products. EX4 ideas board is here -> http://community.wd.com/t5/Network-Product-Ideas/idb-p/network_ideas