I voted for Kael for the combination of practice and the chance to upgrade the gear on some of these characters. I know that most of them are alts and therefore may or may not have the greatest equipment. I know Kael gear isn't that great by today's standards, but it's more than ample for our Leezard Keelers, and some of it is very nice. I also think the arena is something we could handle with relative ease and for that reason alone may be a good starting point.
That said, I think any of these would be fun to try. The revamped Plane of Growth is nothing pretty as many of us will attest to (worst....cr.....ever), but what good is a dwarf warrior if he doesn't have a few bumps on the noggin to show off to the boys in the tavern?
Just to ramble on further....it would be very possible for our mains to go in and kill the protectors making it very doable for our DHers. PoG armor is comparable to Kael or Skyshrine armor without all those pesky turn-ins
