i dont think the exp rate is the problem, its the rate at which you kill monsters to gain exp, adding some basic low level damage abilities, and buffing knights basic tankyness so they can work as blockers without using 500 pots an hour would open up team hunting options a bit
also the lvl 6 healing ability with magic lvl 5 only heals like 4 hp for 20 mana, its not even worth using to heal, just buy pots that heal for 150s and use the mana on light/ammo
think the heal should be buffed to help hunt, i used my full 250 mana to test how much hp i would heal, and gained 44 hp total, means that mana potions are in-ately worthless as well, because your better off with hp pots, heal 3x more for same price
also only mages can use the 'crystals' at level 15, archer is short by about 50 mana to create the fire crystal, which means that knight is probly 200 short, i'd suggest a % mana consumption, or just lowering the total to be useable by all classes at level 15.
on a side note, ive explored quite a bit, and im loving the unique graphics this server has, and the unique monsters im running across in the caverns and mountains spread about sethien.