[Meglobob]

Well...you could create a long term game by having indies at 9, hardest research, money, resources and supplies at 50. Also play on a big map with a small number of players, so each player has 30+ provinces to conquer etc...

Basically anything you can do to slow players down will make for a longer game. It might not be much 'fun' thou.

Other than this you after impose artifical rules, which you hope all players will follow.

Perhaps indies 9, 30+ provinces per player, money/resources/supplies 50 with easy research/maxium sites may be a fun, yet long game on reflection.