I've got (more or less) 1 of each at the moment with 1 spare slot.
1. Asura Guardian <--- Only one I've really played (lvl 80).
2. Norn Warrior
3. Human Warrior
4. Human Mesmer
5. Human Thief
6. Norn Ranger
7. Norn Elementalist
8. Sylvari Necromancer
9. Charr Engineer
10. ???
Huh, multiples of the same profession seems kind of redundant. If you like the Guardian, Warrior would be an easy transition, though I've heard complaints that they're boring (I've never noticed, any time that happens I have a bunch of weapons I can swap in to change it up).
That said, I've also been having a blast on my Elementalist lately, Dagger/Dagger is pretty wild and surprisingly melee-ish for a cloth-wearing caster class. Since Kos and Hawkian have already suggested it, let me go ahead and make it a solid three; give Ele a try.