Not sure how much help I can be. I MTL for over a year when I started vaping, but only DTL for quite some time now. The best tanks for me when I MTL was Kanger Subtank minis and Toptank minis, using the RBA's and a 1.2ohm build at around 14W. I still use them today with a .4ohm to .5ohm at 25W and run the AFC wide open. Works great for DTL for what it is.
I have only used one of my Avocado 22 and only built it with a single coil .5ohm at 27.5W wide open AFC. The flavor is awesome and the clouds are very good. I use the wide bore tip on it.The best I could do to test the Avocado 22 for you in MTL is to close the AFC down to the small holes. Air flow was good for MTL and flavor was great [Alisa's Bust-A-Nut juice], but hardly a good test for you with that configuration. I would think a single coil build 1.2ohm or 1.5ohm at 15W and using the smaller 510 tip would be great. The Avocado 22 has the best flavor of all my attys, not that I have an assortment anything like most of the other folks here, but I have tried many when I hang out at my neighbors vape shop.
I bought a second Avocado 22 to build dual coil, but when it looked like I may get an Avocado 24 soon, I decided to wait and build it dual coil......but as you know, the 24 is still a tease.
What juice blend do you use....50/50, 60/40, 70/30...? I would probably do better if I lowered mine from Max VG for the equipment I use, with the exception of the drippers. I have to turn the 22 upside down all the time to get the max VG to wick [I use rayon], turn my Subtanks back and forth on the sides , and hold the bottle pressed in for a while on my Dripbox's.
There are so many variables to get it right the way an individual wants it.
I don't buy every new atty that comes out. I watch the videos and listen to others critique them, then choose from the ease of building, the design, etc. but even if one person hates it, another can make it awesome......different coils, wire type, wattage use, juice blend, etc.