Aerial Frenzy is more of a skill to help you buy time for your other skills to cool-down
Leveling Guide: Leveling is fastest in mission maps. Plus, you also get Cabal Alz rewarded for your effort. Find a party and head down to these mission maps.
Skills to Take: Your main damage dealer skill is not your Thief skills anymore but Thief skills are rather supplement skills to further support your Jester. That is why for Aerial Frenzy, you will only need (1/5).
Aerial Frenzy is more of a skill to help you buy time for your other skills to cool-down. Cut Down starts to launch your enemies high up at (3/5). Therefore is sufficient there. As for Rocket Punch, max it for a higher rate stun chance but Nosel Tuning is not needed as you only need the stun not the damage.
Burrow the most important skill for a Jester. Use it to dodge, run, evade and surprise your opponent. (1/5) for Burrow, since upgrading it won't do any difference. Rolling Stinger only need to be at (1/5) for stun locking.
Final Decision and Upper Screwdriver are your main damage dealer skills due to the fact that these skills are fast and have big aoes, Claw Mastery at (5/5) for increased damage.
Stance also similar to Claw Mastery is a must max skill. Windmill and Cossack Dance are another addition to your damage dealing skills which can clear both mobs and players out of your way fast.