Hi!
So one thing which is maybe a bit more in the future is that you would
like to peer with other networks. Often this is done through VPNs:
https://dn42.net/Home
https://wiki.freifunk.net/IC-VPN
So and the idea is that you can access each others servers and services
in the network. If you have overlapping IP ranges then that is not
possible. If you use NAT, it is much harder. How I see it, we are trying
to build alternative Internet so we should try to achieve end-to-end
connectivity between our networks. In IPv4 this means that we have to be
mindful about other subnets.
The whole Guifi.net (27k nodes) is using only:
10.138.0.0/15; 10.228.0.0/16; 109.69.8.0/21; 5.10.200.0/21
See the imperfect list of what other networks are using here:
http://interop.wlan-si.net/wiki/IPAddressing/List