I'm using qemu + kvm using libvirt on a devuan server. I only use
libvirt + qemu + kvm to emulate two FreeBSD and a Windows 7 system. One
of the FreeBSD systems is a pfSense firewall, where I didn't configure a
display, but a serial console instead. I use VNC to connect to the other
FreeBSD system. For connecting to Windows Systems, I recommend using
Spice. I have about 14 devuan containers on my server. I really like to
use libvirt-lxc for that, I've written a how-to for it:
https://dev1galaxy.org/viewtopic.php?id=617

Daniel Abrecht