I have a low opinion of WinRoute.

Completely unjustified. Winroute is a nearly perfect piece of software for a Windows gateway. It is lean and mean and extremely functional. A machine can be made a ghost to probing, and all the computers behind it. It does not hog the processor(s), it has blazing performance, and a simple but functional administration interface. For the fun of it, it has its own DHCP server and mail server. The former allows faultless synchronization of the NAT table. The latter could be used specifically to route administrative information from machine to machine.