A strong economy is important whatever style I'm playing, I usually go with a random nation as it forces you to change your gameplay a little.

If I start off too close to someone I'll go for an early war since I know it will have to happen sooner or later and then the tactics depend on the geography really. A larger exposed border with an enemy means I put more into military where a bottle neck city means I only need a few units around.

In the end money wins, you can buy military units when invaded or buildings in peace time. Sometimes I buy settlers early on in the game so my cities can grow.

Religion is one of the best ways to ensure that sort of income if you choose the right bonuses.

I've won domination and cultural victories, never been very good with getting the voted in as world leader though.