Apologies for more email, but I would just like to throw in my own (very simple) personal opinion on this topic. I strongly believe that the correct solution is to divide up the IP address space geographically (ie by country), and then simply give out allocations, regardless of purpose, as is the case already both with 44net and the rest of the IP address space.
This gives people the flexibility to use the IP addresses in whatever way they see fit, whether that be a well known radio protocol, an experimental radio protocol, a tunnel, an experimental wired protocol, or just Amateur radio related services on the public Internet.
Let the users, who are technologists after all, work out how to route traffic based on their own needs. Any attempt to artificially carve up the address space by purpose will only further confuse matters. There isn't a single unified 44 network, and not everyone who runs by RF necessarily wants to be connected to or disconnected from any other network, including the Internet.
Charlie