I think Hunter is a good choice for Midgard at least (and presumably Ranger and Scout in the other realms). I am capable of killing mobs fairly quickly and steadily be it in a TD or in TOA for instance. Of course its easier if you have a shaman to buff and heal but its possible to farm with some consistency without one. I am currently working on my CLs and MLs by farming for glass in TOA, mostly solo but sometimes with my wife's shaman to back me up. Just make sure you spec 50 Bow. I wouldn't say its easy without a bot/partner mind you, but its possible.
A Summoning SM might do well too, but I doubt it would be as fast as my Hunter.
The game has been balanced based on the expectation you will have a bot account running - or be grouped up.
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Sneev (SM), Rhejan (Hunter), Skraeling (Warrior), Fulkk (Healer), Erlennd (RM), Hasting (SB), Nithling (Cave Shammy) - 50s
Hratlann (Skald), Grimstainn (Shaman), Sighildr (Valkyrie) - up and coming
Asarna's Arme