LAN play uses the same favor pool as the single-player game. If you look up the "game.prefs" file and open it in notepad, you'll find a line inside that says something to the tune of "Points = [value]" ([value] being the number of favor points available). Change that value to whatever you like and whoever plays on that system will be good to go.
It's been a while since I've done this but if you can't find that file right away, you might also have to run the game once before it actually shows up.
