Rogue, Pirate and its variants:
Give them your best Thief enhancements. Before entering a battle, make sure you buff up with Footwork. If you have enough haste, you can use up to 5 Opportunity Strikes in a row before Viper's Kiss wears off. At a high enough level, you can do this twice before Footwork wears off. You should also be evading about 75% of all attacks dealt, healing you for more damage than you take. Speed and timing are the key to mastering Rogue/Pirate/variants!
At level 35 and up, have 2 Lucky enhancements on either your weapon and cape or your weapon and helm and have Wizard on your class and the other blank slot. Make sure your enemies are always Scorched before anything else. Time your attacks and maximize cooldown; use your skills in the order of longest cooldown to shortest cooldown. Don't go trigger happy, though. Make sure you always have enough mana for Flame Orb; a single crit from a well-timed Flame Orb can get ALL your mana back in 1 hit!
Give your weapon a Lucky enhancement. You can play Chunin 2 ways: Offensive or Evasive. Give it Warrior enhancements on its helm, cape and class to deal the most amount of damage, hitting for crits 1/3 times. Or you can opt to give them Thief enhancements and have really high evasion making you practically untouchable with Paralyzing Wind in action.
Get Chunin to rank 10 ASAP. You won't be able to solo without its rank 10 passive, Ancestor's Favor. Forget Chi Blast and focus instead on Tsunami Strike and Paralyzing Wind. In case Paralyzing Wind fails to hit, take a chance and hit enemies with Spinning Dragon. Take note of your mana and whether you miss or not; this can turn the tides of the battle. Bringing health potions is highly suggested, if not, pair it up with an Evolve Shaman or Paladin.