[Messianic]

AE groups really aren't all that effective until you get your first Jyll's at 53. You're stuck with quad kiting until then, which fortunately is pretty darn effective.

I got great exp quadding Mammoths in everfrost to 31, Undead Skels in Rathe Mts 31-34, and there are an absolute ton of places 34-low 40s. Bloodgills in LoIO low-mid 40s through 49-51 (I preferred spirocs 49-53). After that quad kiting is terribly slow and locations are limited, so AE groups are a natural segue.

Edit: Aggro kiting in a duo is pretty darn effective with a rogue. So there are other options; quad kiting is just the most glaring option.