list your best no nonsense grind XP zones

[Galanteer]

You can start soloing Kedge entrance at about 30 (at least for mages) and a little higher for charm for enchanters. (they have low mr so charm tends to stick)

note: my experience stems from live, not high enough here yet.

edit in: at 21 your likely best in MM, there is generally a bunch around there to group, and enough easy pickings to solo. There are other good places like Uguk and Loio that have some people about if your looking to group.
edit in: you could try Oot for a bit -gargoyles (good money and exp) then goblins.