[OT]    I would prefer Mdev if the issue with X11 could be solved :-) 
Mdev is so simpler than Udev, Eudev and Vdev.

     Let's forget Systemd and their "solutions". Interface renaming was 
introduced by the original Udev. According to Adam, it races with 
kernel's device discovery and the only solution is apparently to use a 
namespace different of the one of the kernel.

     Note that a similar problem with disks has been solved elegantly by 
referencing disks by their uuid or label in /etc/fstab. Maybe 
/etc/network/interface could specify the MAC address as a hook. This 
would only suppose that the hotplugger creates a symlink to the 
interface in some /dev/net/by-address/ subdirectory. With this solution, 
it is up to the admin to decide if  s?he wants a simple configuration 
based on interface name (eth0) or a secured one alla 
"Address=a0:d3:c1:9d:a5:86".

     Didier