There is a decent amount of activity on Excalibur, though like the previous poster mentioned, I have no frame of reference since I haven't seen how other servers are. There's usually a lot of shouting in Ul'Dah for parties for various things, so I don't think it'd be that hard to find parties for leveling and other tasks. It's waned some since I last actively sought one, but there are always plenty of people on to team up with.