ahman
Warlord
One more thing. People usually say expand towards AI first and only after that build cities in your backyard. I don't exactly agree on that. While in later game phase(starting from medieval) the strategic choices are more important(taking land from AI), the first 2-4 cities should almost all the time follow the rule of return of investment. Of course, food is more important(you can do a lot of stuff with food - rushing, workers('storing' population + developing the land), bigger pop when using lux rate etc). When you have solid core, the military takeover is much easier. You will attack other nations, you will take over lands. The only time expansion towards ai is a bigger priority is when you won't wage war for a long time.
Sometimes I like playing with 80% water, to get nice chokepoints. If you get a good start you may be able, using a couple of warriors or even workers, to block the settlers trying to pass through your territory.
In that case, expanding towards the AI first can get you a couple of more towns, each giving 4 military upkeep. That's nice because you can't expect to build many towns on a 80% water map before you get surrounded.
But if i think of it a little more, you can go and block the AI without building a town. So never mind

I want to play at the higher levels, but I get destroyed or, if I am lucky, they are 6-10 techs ahead and twice my size.
On a pangea map, the opponents find each other very fast, trade techs and leave you behind. Try archipelago and a civ starting with alphabet (commercial or seafaring), build a curragh after your first warrior and start finding AIs. You'll be the king of trading through the ancient ages, before they start finding each other, and at that point you should have a nice army to start extorting, or a nice peaceful empire focusing on research.
My experience is that getting happiness from multiple distant, harmless AIs declaring war on you, can give A LOT of extra money. Having the luxury slider at 0% is very nice. It's worth it, because on archipelago they'll send only one galley at a time. Harm the galley with a couple of catapult shots, then kill it with your own galley. Or try to control where they land by leaving one city undefended. Or ally with an AI that's between you and your enemy, and you'll never see them, they will attack the nearest enemy. Free happiness for everyone!
Sorry for the rambling, I'm getting too drunk. I think that most people agree me with though, that archipelago is much easier than pangea on the harder levels?