Seconded on the tizmaks in GD. They are super chill. I quadded them on my druid starting at 34 to like level 38. Never camped, but you'd get your ooc chat.

Around levels 38-45 you can camp the Skyfire ramp in OT. Free buffs from all the people looking for ports and basically unlimited mobs roaming the area. If something FKs up a rez is not hard to get either since its a port hub and clerics travel through regularly due to OT hammer.

There is enough room you can solo comfortably and enough chatter that you feel like you are actually in an MMO. The mobs are also essentially endless