The most significant improvement comes from the BootFromTemplate, which improves speed and saves memory. And the boot sequence and guest kernel have been optimized.
What do you use for storage, how is the hosts storage accessed from the guest-container? virtfs?
Doesnt that add a bottleneck/performance-problem, even if youre using virtfs thats several layers of translation from VFS/block-device-virtual(what kind do you use?)/PCI-bus to VFS/block-device/pci and so on.