Well, libvirt-bin seems to JustWork with the one exception of not permitting ingress traffic - but then kvm has the same issue.
It seems to me that fixing libvirt-bin to have a mode where you get bridged to the container/vm + NAT for ingress traffic would help lxc, kvm etc - better than just helping lxc, and shouldn't be any harder.
Well, libvirt-bin seems to JustWork with the one exception of not permitting ingress traffic - but then kvm has the same issue.
It seems to me that fixing libvirt-bin to have a mode where you get bridged to the container/vm + NAT for ingress traffic would help lxc, kvm etc - better than just helping lxc, and shouldn't be any harder.