Unstructured P2P [Steamworks]

[twilit phoenix]

Basically you want to use more of a P2P architecture. FishNet doesn't do this, it only works with a client-server architecture. While it may be possible to set up multiple connections from clients to other clients, it probably isn't a good idea.
If you don't want cheating then you don't want client hosted games. You could have a dedicated server for verification of certain things, but in reality you are much better off using dedicated servers for the games themselves.

[main dew]

too expensive, i checked with my type of game (like in lobbys and worlds) up to 200-500 players on a server, it would get very costly very quickly by what i saw from testing with 10 vs 20 people