Dawnshroud Peaks was basically built for beastlords. It gets tiring, but it's good experience.
Levels 25-30: Set up camp near the Sanctus Seru zone. Pull the three spawn of shrooms, and if you're beating them out you can also pull lightcrawlers and small zelniaks.
Levels 30-37: Move over towards the opposite side, and set up in the clearing right in front of the shroom spawn there. The rockhopper caves and merchants tents will be just to the north, and the tribal spawns will be to the south. Pull the regular zelniaks. You can start killing large zelniaks at the Neth zone if you want, but regular zelniaks give the same experience at this level and are half as tough.
Levels 38+: Large zelniaks near the Neth zone, or wherever else you can find a nice concentration of them. People like the tribals as well, but I never cared for them. Large zelniaks carry you to 42 if you want. Maybe higher.