My attempts to play on Empire (very hard) difficulty have so far not gotten off to an auspicious start. Mostly it's a case of me not feeling comfortable with my game setup choices. I initially played the Ottomans, but I couldn't figure out how to parlay their naval advantages into victory. Then I started a new game as Venice, and while I was fortunate enough to get a coastal start, the random map I chose turned out to be a Pangaea, so I'm not sure I'll be able to win.
I have a confession - I was pretty sure I'd be able to win on Emperor. It's a little embarrassing to discover the limitations of your own abilities, especially when you thought they were greater than they actually are.
I guess I don't actually have to win to enjoy Civilization V. I didn't win at first, and yet I stuck with the game for hundreds of hours. So, really, this is just like starting over. Maybe I should look at this as an opportunity to rediscover the game and see it through new eyes. On the other hand, my early view of the game was from a perspective of constantly being upstaged by the AI and uncertainty about things like build order or the proper direction for expansion.
I expect a few more "practice games" will sort things out. All I have to do is learn to manage my expectations and lose with dignity and grace. . .
It should only take another hundred years or so.