A revised matchmaking system is coming out in the next update which i believe is at the root of all this evil lag. One can only hope anyways. They are going to tweak the match making system for parties only i believe for right now. From my understanding what they are going to do is make it so whoever the party leader is, that is who the matchmaking parameters will go by. So in theory this should give the advantage to the party leader. When asked when this update is coming Ghandi replied within a month. I do know that when i play by myself i tend to have better games then when im in a party, so even though it wont be perfect its a step in the right direction.
For some reason whenever I am party host I get match made with all the spanish people even though I live in the North east of England >_>