the server discussion reminds on an older discussion in the sauerbraten forum. p2p
so here an idea maybe suitable for the future:
as most people will run PAS servers from home, we should think about a kind of hybrid p2p server which could make it easier for all the people who are behind a firewall to bring their stuff online. i think most people using PAS dont want host a server permantly or rent a game server, btw nobody does it at the moment. they just want to show their work to other people, doing coop for a while or sharing maps (+game content) ingame, which is not possible at the moment. hybrid p2p means that you can publish your map. You will be listed on the master server, without starting a server by your own. from here you can invite guests or they can join by their own (if wanted). while all the connecting stuff is done by the masterserver, we dont must care about nat and firewall. for channel 0 and 1 (positions and server messages) the client will act as server too, serves all guests. real p2p comes into game for channel 2 (sending receiving maps (files), maybe later for complete gamecontent).