Maybe I'm the only one to think this... but my best games since I have BtS have been those that I started in the middle of several civs, or completely isolated. I usually play Big and Small, or Medium and Small, all the rest random. Another thing I do is to keep a save at 4000 BC. If later I give up or lose, some weeks later I try a different approach. And sometimes this lead me to a victory, often in a way I did never expected (like going for space race with romans, all peaceful along the game; or making a ax rush with indians).
Some hints on my experience (and don't think on me as a deity-player, I just play on Noble, and it's a good challenge for me):
-Check the War Academy articles. They're great and help a lot.
Now, my experience:
-If you start surrounded by enemy civs, find out who's closest to the sea. Yhat's you target. Just one city on the coast may give you the possibility to create a great empire far away from your starting point. Remember to bee-line for optics, and don't trade it. You'll be able to spot some places to settle. If you saved a great engineer, you may build one of the "Palace effect" wonders, and ta-daa, you have a new starting point, backed by your former empire. If you think in history, you have the British empire. Try a game in the world map, with the english starting at their historic site, and you'll get an idea of what I'm talking about.
-Another thing to do if you're surrounded by enemies AND there's no zealot civ around (say Isabella, Zakub, Monty, Saladin, etc.), you can just go all over the game without SR. You'll easuly become the trade king, everybody will love you, and you'll get lots of tech from everybody, what gives you the possibility to go for space race, or for a diplo victory -and a victory is a victory. More than once, getting a dippy before someone builds a spaceship makes you feel better than conqeuring the world.
-If you start isolated: settle in the coast, and bee-line for astronomy. Once you contact any CIV, turn to no SR, and follow the said above.
Hope it was useful!