Y'all will have tons of fun!
I think it is more likely the game will last approx. 5 - 8 years (through turn 88 approx.) It will be hard for any particular player to control 3-4 VP provinces for long unless the other players are not paying attention.
There is 1 VP province per player. So, players need to scramble to prevent any particular player from grabbing too many of them.