I fly mine brawler all the way. Double Carronade/mortar port, Double Hawacha starboard.
You've got your 'disable' and your 'kill' side.
Usually, you want to bring Kerosene, Chute Vent, and Claw for your pilot tools.
The most important thing with this build is to catch the enemy off guard. Fly in quickly at an angle with Kerosene (Galleon has a much higher top speed then most people expect, it's acceleration is just the crap part. Boosters take care of that nicely) when their attention is elsewhere, and open up whichever broadside is easier, your call.
You're probably going to want to focus on kill side, though.
Tell your lower-deck to open up on EVERYTHING.
I like to tell everyone downstairs to bring Incendiary. It guarantees that the enemy gungineer will have to come off his gun to help with fire control across all decks while the main works on the balloon, or vicea-versa.
Congrats, you've not only got the enemy pilot panicking because 'HOLY CRAP, SUDDENLY GALLEON BROADSIDE,' the engineers are panicking because 'HOLY CRAP, EVERYTHING IS DEAD OR ON FIRE' and the gunner is panicking because nobody is extinguishing his gun.
The pandemonium doesn't last long, because assuming your main engineer can ignore his/her responsibilities and stick on the mortar, you'll net a kill so fast, you'll swear you're playing Call of Duty.
And if your prey's ally is nearby, but was too late to save his/her friend, you're ready to completely disable with a double-hawacha. Your ally should swoop in and get the easy kill.
Well, in theory.
It usually ends up going something like "AH! KEEP SHOOTING! NO, NOT YOU, GET ON THE HULL! I'VE GOT BALLOON, TANK THAT HULL! NO! NOT YOU! KEEP SHOOTING! WHERE THE HELL DO THOSE ARTIES KEEP COMING FROM?!"
But douse me in water and call me Janeway if it isn't a hell of a good time.