Personally I always choose knight and head straight east down the stairs for the Woodlings, Troll-trained Salamanders, and Meadow Striders.
- Woodling- 80 health 40 xp
Can loot Studded Shield (Def:15) and Studded Armor (Arm: 5)
- Troll-trained Salamander- 70 health, 23 xp
Can loot studded helmet (Arm: 2)
- Meadow Strider- 100 health, 50 xp
Can loot longsword (Atk: 17, Def: 14)
You can loot better weapons and equipment to help you kill quicker.
You can get a constant spawn of creatures and don't have to go far to find more which is important since your character will be slow.
You don't need any additional tools like a shovel or additional potions.
You can easily manage the spawn by using trees to block sqms incase you lure too much or just hop up the stairs.
It takes me about 30 minutes to get a character to level 8 this way.
I hope it helps!