I havent been playing on Classic much since I upgraded.
But It has a lot of different people on it so its easy to find people to talk to or whatever. There are a lot of quests even if some of them are a little easy at times. There are all kinds of NPCs at the time I have like over 30 or something. Well...its fun
They also have a ring that lets u dive underwater
and it brings you to a whole set of underwater levels.
Classic is very much fun