There's many different and subjective factors that might be at work. I prefer RDAs over RDTAs because of this problem, for me "tanks" don't offer enough for flavor. I'll get that out of the way, "you're using a damn tank, that's it, switch to rda instead.:
Kidding aside it might also be in how you're wicking it. I've been recently 'playing around" at defining a
good standard of how to wick near any build so to get flavor. This morning I had to take out half a load of Muji Cotton that I let get burnt in a Wasp Nano. That was on me too, I just hadn't found the sweet spot for how much cotton is
too much, too little ... too little.
If you pack the inner diameter of your coils with too much cotton you'll block juice flow. This even happens with Rayon for wicking. The fibers, in either one will start compressing on themselves and become
walled up. Rayon does that a bit less but it can still do it if you pack dense. No juice, ya got no flavor no matter how you chuff on it.
The trick lies in cascading your wick material. Make it have
shoulders up toward either side of your coils. Then, it comes off looking like a waterfall. In the juice well you'll want it thinned out to look like tree roots. This saps the juice up thoroughly and provides an even flow of it. Your shoulders will of course, compress and let you have a naturally/organically formed hole through the coil. The wick lies on the bottom half of the coil. You don't want to think, "okay I'll fill it up." The air going through the coil also helps in keeping the juice going.
It also might be your juice isn't mixed to do top shelf flavor. Look for juices with more of a PG ratio as PG kind of was designed to carry flavors. VG? It kind of lets you get bigger clouds, although if you get a good mixer doing up flavors in VG you can get real nice flavors. It comes to ratios and experience in the mixing. So you can try that as well.
You might also try about 1/3 of full air flow on your atty. This though is more about what you prefer, tighter draw or looser. Smaller airflow gives you tighter but it can also give a boost to flavor. Full air flow can boost flavor too but it's been kind of tricky for me to use it like that, not saying it can't be done merely that I'm having difficulty in it.
Hope I've offered you something of help. Just a lot to getting flavor where you want it. When you do, you'll know it and that'll be your
setup from then on.
If I've not helped, bet my buddy Bob can.
@The Cromwell Or even
@JuicyLucy .
ETA: Apologies too for the poking fun about a tank. I looked around there is also an OBS that is an RDA and not a tank. Fuss at DuckDuckGo I read the first one or three links it spat back, only saw an OBS as a tank. Damn hard to keep up with everything out there anymore. Glad there's choice but at times it gets like "go to the store and buy me corn cereal." *stands looking at the full aisle of corn cereals in all kinds of varieties*
Mmm, yummy too even for unflavored juice. Nice for DL and/or MTL. 