Game-wise i agree with DrPret. Accumulated VP's are the best winning condition if set right. It might be difficult to guess where VP limit should be on a 62 player game
.
Acc. VP's will encourage war and make long lasting treaties with weak neighbors less interesting. Something that is probably needed in a game of this scope.
Or you will have to be clear about who's servant and who's master by giving your Lord your VP lands.