Do you think Nexon made a mistake with vindictus?

Er... That's not how it works. Nexon is still the "host." The leader of the party is heavily depended upon when it comes to the connection, and unfortunately, strength of their computer to reduce the strain on Nexon's servers. However, Nexon's servers are still the host of the game. Unless you manage to find a way to host a party without connecting to Nexon's server in the slightest bit (which is ilegal), Nexon will always be the host.

Thats good to hear.