Paluto caverns will always be a place to go to level to about 18 the experience is always good. The best thing to do is go to the hot zones and level. I am not a great soloer but I can ok with my druid. Wish I had more to say but it has been years since I was in the lower zones so I really cannot remember the ones that were great in exp. There are the Experience zones and you find out them from an NCP in POK right by the gate in point by the guild lobby door
\good luck