Having never used Boxes before, I was excited for a better VM management tool than virt-manager.
However, I just tried using it (on Debian stretch), and unfortunately I have to agree that it doesn't do much beyond look pretty.
afaict you could only go to consoles, check a few resource usage graphs, send power commands and manage snapshots. There were very few configuration options and no ability to manipulate virtual hardware on existing machines.
Also, there was no way to add remote libvirt instances from the GUI, and adding them into the config file (qemu+ssh) just made boxes crash.
If virt-manager really is going to be deprecated, is there a good replacement out there?
edit: Holy crap, it also managed to hibernate all the running VMs on my dev box when it crashed!?! Glad I didn't have anything too important running on it!