...warcraft 3 does something different, and better...
as for the host, a good host produces low latency, about every game of demigod has a lagger that ruins it for everyone, in war3 ive had many many many successful dota games
Actually, in terms of the structual make up of the networks, Battle.net - Warcraft 3's connection system - does very little different compared to Demigod's system, except that it's 10 years older and about a million times it's size. It's been refined for literally a decade. Of course it's going to out perform a system that's actually younger than the game thats running on it.
And in P2P situations, in terms of overall latency for all players, the host doesn't have much impact. Doesn't matter who hosts a game, it only matters where the players in that game are located. This is not server/client, this is Peer 2 Peer.
What will cause issues is upload Speed - due to the nature of Demigod's network system, which doesn't use Proxy servers to the degree that Warcraft 3 does, more upload is required than in most other Peer 2 Peer games. It's not really Demigod's fault, however games that use systems like Battle.net mask the issue with Proxy servers as less connections per person are actually required. This issue has been discussed several times on the forums already and nothing new will be gained from discussing it again.