to be honest i can't answer you questions because i'm only level 27, but what i recommend is give the game a try, the first month is completely free. and when your time is up you will have 3 options, 1. if you don't like the game at all simply quit. 2. if you enjoy the game but don't want to pay monthly, you can play for free every weekend. 3. resubscribe and enjoy the game.
as for servers i play on Cerberus EU very friendly,active English speaking community, though from what i hear odin and moogle are the most active EU servers.
hope to see you soon =)