You're absolutely correct though. It's not really KVM's fault. It's the Linux iscsi, software RAID, and volume management capabilities that are so lacking.
It just happens that that makes using KVM much less appealing.
1. Reliable Snapshots and Replication
2. Simple Volume Management
3. Human readable device names
4. Consistency of volumes/devices between reboots
5. An "uncorruptable" FS backing the guests
6. Reliable Virtualization
FreeBSD may be a good fit with VirtualBox, but VBox on OpenSolaris and OpenIndiana was unstable for me at least. I'd like to give FreeBSD a try sometime.
On libvirt, that's about what I expected. I guess I just wanted to complain about it in general. ;-)
sudo xm new /my/config/file
sudo xm start my_guest
sudo xm shutdown my_guest
sudo xm delete my_guest