Level 18-19

[Expediency]

Oasis is very popular at that level, but if I were you, I would absolutely go to upper guk no later than level 20.

Benefits:

-Very high experience modifier
-decent vendor loot considering your other options
-zone isnt abandoned, there will be others to group with
-People pass through to get to lguk so rezzes/ports are possible

There are several good places for you, go down, take path to the right, swim around to spiders, then stop to fight as soon as you encounter blue frogs. The spots near the lguk zoneline are some of the best exping I've done on this server you can safely chain pull