Closing off the airflow a touch will produce much better flavor. I run my Avocado strictly in single coil mode, and I have the front cyclops slot about 75% open, and the hole in the ceramic block fully exposed. The draw on this setup is perfect, a nice, somewhat restricted lung hit. Also, the use of the smaller standard 510 drip tip, in lieu of the larger bore drip tip will enhance the flavor a touch. This will restrict the airflow even more, giving even better flavor. On another note, how you wick the coils can have a large effect on the flavor they produce. Too little cotton will give spitback usually, and too much cotton will produce dry hits easier. Finding the delicate balance is KEY for maximizing flavor potential. Also, as with all RDTAs, the amount of wick that hangs down below the deck and into the tank is important. You want smaller "tails" hanging down into the tank. I generally have the tails hang down ~3mm below the deck's wick holes. Tilt the tank with the coils facing you as you vape, and the liquid will wick constantly as you vape, never giving you a dry hit, as long as your wick job is decent. Lastly, ceramic coil heads will produce superior flavor to standard 24g KA1, so I can see why you were skeptical at first...However...Claptons in single coil on the Avocado will produce MUCH better flavor and vapor than ANY ceramic coil head out there. I usually rock a 2x26g core, fused with 36g KA1 fused Clapton, 5 wraps around a 3mm bit. Ohms out around 0.4ohms. For even better flavor, I will parallel the fused Clapton with a single core Ni80 Clapton, producing a staged heating coil effect, and creating a HUGE coil surface area, mimicking a 10 wrap single coil, with the lower resistance of a 5 wrap, due to the coil being in parallel. Again, ohms out around 0.35-0.4ohms. I vape it around 55-60W, and the vape is GLORIOUS....can't beat fused claptons when it comes to flavor on this atty. Well, Aliens are slightly better flavor, but a BITCH to build....if you can get your hands on some prebuilt Aliens, I recommend those in lieu of fused claptons.
CHEERS! And good luck to ya pal!