Not sure what level your playing on, ive played 3 games now all on regent... the first game i was behind tech wise, the last game i abandoned when i got so far ahead it was unchallenging...so onto monarch for me now.
The main differences in my style of play are not dramatic really...
more workers
DONT over irrigate... if that city has excess food, is size twelve and your a way off hospitals.. then get some mines down!
I tend to put cities closer to get more from my land ...again 12 is max size for a long time so some overlap is fine for a while
I do tech trade, on MY turn
and if an island map put a bit of effort into getting contact early..
Civs...i like archipelo maps 70% water.... i find the english do extremely well on this map... ive read man o wars are underpowered, but i love them, they rule the seas for ages, and make a Golden Age easy to trigger.
Anyway i have only played a few games, and i probably am not the best to advise,but thats how i went from struggling at regent to finding it too easy..