Ohnar West, if you like the possibility of destruction in the event of a political hiccup.
Kindara is a safe bet, if not a little slow. We try to keep new knights around. Zonasa is probably the same way.
Arcaea is the safest bet, but the downside is you'll never have the chance to fight Arcaea.
I don't really know anything about Greater Aneilia, Sorraine, or Coralynth.