Arcangrove
This place is good for farming exp because the monsters give you over 200 exp per kill.
Ebilbattleontown
The monsters at ebilbattleontown give you over 400 exp and sometimes over 800 exp per kill. (800 exp per kill is very rare.) This place will go rare though after the event is done.
Hyperium
This place is good for farming exp if you can kill the turrets. The turrets give you over around 1,000 exp per kill but can do over 10,000 damage to you and kill you instantly. Also, if you haven't been there before and just go there, if you cross the line the turrets will kill you.
Pirates
This is a good place to farm exp because the monsters give you around 400 exp per kill.