I found Vermin Snye a good place for soloing and grouping. If you pick the right area such as the corridor around the Ravenous Cubes, you can do alot of damage, get some good exp, and get some good chest drops. It is also a good place to find a group as heading into the mid twenties there are still things to fight there. Be smart, use your HO's properly, learn the zone and you will do well.
Mal
19 Crusader