pdu81, its not you vs 3-4 its you vs 3 vs other 3. So they are balanced out with a little luck. Some of them are allies, so one of the 3 team don't attack each other. The art is to know which one of the teams is winning and weaken that, since when one of them is winning over the other, they'll then roll over you.
bloodofcrom, I just did it in 23. Tips. Expand whatever you can, take france. If the enemy has a strong army do not dance around it, but go directly against it (with a larger army). for example southern france Then take spain, portugal then go through rest of europa. Maybe give one of the 120 stacks your partner. Late in the game its ok to betray your partner otherwhise he might waste turns in getting the last nations of the enemy.
Can you please do it, that if you attack an territory and your teammate takes it first, the transfer just fails? I had moved my big stack towards the enemies big (but smaller) stack and my teammate AI takes over the stack, just idiotely spreading it thin instead of using it to destroy the enemies army (with great ratio on our side).
Somehow it feels, this was a really sweet, good singleplayer game with its own kind of flair, that was late in the productioncycle cluelessy tranformed into multiplayer due to more money greed. (clueless additions are: thugs, improvements have to be from other players for no deeper reason, broken guild system, no guild chats etc.)