One potential wah to fix things might be to go to a one player per country, at least as far as government goes. Maybe we can work a system for private citizens like businessmen to meddle and plot.
Another thing that might help is to introduce a character creation 'system' where you can pick say two benefits and a weakness. So maybe Jean Patrique O'Dea would have being very dapper and wealthy as his advantages, and a habit of overindulging in coca leaves and absinth for weaknesses.
Possibly something similar might work for countries, I.e. a great power can have x number of points to spread among y stats. We'd sacrifice realism a bit but settle a lot of haggling over what is 'realistic' for this and that.
Another idea would be a more substantial shift in focus, where the players are all part of the same steam punk state, competing and conspiring with on another.