the random selection of teams is great but how many? two? three? and perhaps(if the team number is just two)then the first two cities can be split
City #1 goes to team #1
City #2 goes to team #2
and the two teams go on their separate ways but they are still required to help out the other team if need be. The two cities would spawn of their own cities (with their own workers) and the wealth can be calculated from each city that goes to their respective teams so teams would have a budget and would spend accordingly
e.g. Team #1 gets 3 and then team #2 gets 4 gold total 7 gold but team #1 can only use 3 out of the 7(obviously) borrowing and all that can be done but the teams would have to pay each other back and what not... not sure if this would work though because tight records would have to be kept of money and people might get nasty about who has how much gold all the math people out there would be happy i guess
but this would give the game some heavy competition, random selection of teams of course.
comment would be really helpful