I think people also need to realize that there is much more than IP to work with. Sometimes we get so locked in on one piece that we forget the rest of the network stack.
I've been thinking about this over the past few days and I think maybe that's where D-Star possibly got it right by just exposing Ethernet to a radio interface. Because then you can segregate traffic by VLAN and use Bridging to build your networks. VPN's are quite capable of Ethernet bridging which allows for all sorts of traffic - including routing protocols. VLAN's would also allow for segregation of traffic by content type so that if you didn't want global internet traffic on your network leg, you simply don't subscribe to that VLAN within the internal 44net.
Bridged VPN's are built with UDP connections but most home routers understand how to handle this type of packet making it easy to expand the VLAN's. Even if you were behind a firewall or double-nat, you could use TCP and routers on both ends to route traffic between dissimilar networks.
IP ingress/egress from the public internet would then be up to entry/exit nodes who may or may not advertise a default route that reaches the internet. Thus, those particular gateways would have to filter/restrict as they see fit. They could also allow ingress/egress based on VLAN so let's say you have a WX/Weatherspotting VLAN that you want to have access to Meteo/NOAA information but nothing else, you could do that and not affect anyone else. If you don't like the traffic or want to do it your own way, you can simply change/remove the VLAN tag or just override with a static route or use iptables/firewalls.
But ultimately, people should treat 44net the same as any other shared network. Like what is told to people on another private network I'm part of when signing up, "Thar be DRAGONS!" and the network should be treated as such.
Ok... go ahead and poke at this one... :)