I’ve been playing Serenissima recently -- one game with 3 players, and a few with 2 players. I didn't get much of a feel for the 3-player game, but I've developed some thoughts on the 2-player game.

The first problem we found was that there's a huge incentive to attack each other's ships. After all, if you win, there's a huge reward -- you opponent loses a $500 ship while you gain it. In the regular game, it's not so worthwhile -- if you win with enough men to capture the ship, you'd have 2 out-of-place ships which you can't reinforce, so they'll be "viking bait" next turn. But in the 2-player game, there are fewer predators around, and there's more relative advantage to hurting the player you attack (their loss is your gain, while in N-player games, this isn't nearly as true).

Soooo -- first thing we did was to make ship-to-ship combat less attractive. Ships, in effect, are like forts -- divide by 4 rather than 3 to figure your losses. This seemed to work well -- the game once again reverted to primarily one of plying the waters of the Med gathering cool stuff -- rather than a pointless combat game.

The next problem was turn order. Normally, you bid for who gets to go last. However, the advantage of going last can be so great, esp in the 2-player game, that it became an unbalancing mechanism -- whoever is ahead can afford to always outbid and thus go last, ensuring their lead. In an N-player game, at least there are other players to help bring down the leader. So, we felt some balancing was needed here for a 2-player game. The first idea we tried was to say that only the winner of the bid had to pay -- the loser keeps their money. This worked reasonably well, actually. The leader can pay to continually move last, but he will have to pay more for the privilege (in relative terms).

Still, we didn't much care for the asymmetrical nature of this mechanism. For one thing, it just doesn't make intuitive sense -- as if one player has a satellite system, and hones in for specific attacks on the other side of the board with their viking ships (a "viking ship" being a boat loaded up with 5 men). So, we tried a simultaneous-move system. First, you roll for turn order -- no bidding. This establishes order for everything except movement. In practice, we'd both do our builds simultaneously (but one player has the privilege of final adjustment). Then, we'd write our orders down for movement. This didn't take too much time -- you only have about 5 boats on average (fewer at the start, more at the end). We would then execute our moves in order. The final stages were all done in order, as per usual.

We're not totally sure of how well this works. On the one hand, it eliminated what was an annoying aspect of the game for us -- the gaminess of the moving-last privilege. On the other hand, writing orders is more difficult than simply doing your move. Of course, you can both be working on your move at once, so that mitigates against an increase in play time. Not totally decided on this one, yet... Anyway, it seems to me the simultaneous-move system would work quite well for 3 and 4 player games, too.