Hi There, I have 977 hours on this game, and I'm often successful in multi-player sessions. Here are some things you should take a look at in your game. * Advisor Council It may seem like something that isn't really helpful in single player, but in Multiplayer, it can often keep you on the right track, and aware of who has a strong military. * Demographics Another thing that can be useless in Singleplayer as most people tend to snowball ahead of the AI. But in Multiplayer it lets you know where you stand among the rest. * Worked Tiles All experienced players know how to micro-manage their Cities. Making sure that they are properly utilizing their resources. * Specialists Just like worked tiles, specialists are very important. They allow you to utilize special buildings to unlock a higher potential in your city. * City States One of my favorite features of Civ 5 are the city states. They can really shape a game if you ally and use them. I once I had a game where a wall of city state allies protected my civilization from an advancing war monger horde. They can also give you boosts to Food, Faith, Happiness, Culture, and Military might. * Social Policies Nothing can improve your gameplay more than selecting the right policies. If you're using Piety on the Byzantines, you can end up very powerful by the mid-game at the latest.

Let me know if any of these things help you out.