Just que up for a random dungeon in the dungeon finder. Rested XP, in addition to any guild bonuses to XP, will add up fast in a dungeon.
The most invaluable aspect, in my opinion, would be learning the mechanics of a hunter in a group setting. Traps, pet management, movement and are things you can get to know better when running with 4 other people who might rely on you to prevent a wipe.
Battlegrounds provide some player vs player fun and also provide some experience. There's also daily fishing and cooking, in addition to archeology. Side professions are a good way to get experience, as well as gathering skills, which I believe also offer experience.
Good luck.