I've been vaping for a year-and-a-half now and I had the same problem with my Kanger sub box Mini on the beginning, not knowing much about vaping I figured the flavor that I was receiving was As Good As It Gets at least for the setup that I had. I asked around to see what the best setup was and kept on hearing the crown tank but after purchasing the rx200s mod with the crown tank, so i got it amd the flavor was still very muted a bit better but still very dull, it didn't taste burnt it didn't taste like cotton it tasted like flavorless vapor I couldn't even feel it in my lungs even though there was lots of vapor production for some reason even the vent holes when I would pull sounded and felt very rough insted of open quite and clear. I kept on telling myself well....I guess this is what vaping is? But it didn't make sense from all the YouTube videos I've seen on Ejuice and people talking about how delicious and juicy and flavorful The Taste is plus all the artwork that goes into these bottles not to mention how huge The Vaping scene is these days..... I knew something was missing, that I was doing something wrong. When I first started vaping I bought from a smoke shop not a vape shop, (first mistake)
So because of that I was given very very very little information on how to start vaping. And since day one it is been nothing but trial and error from anything you can think of tank, wattage, coils, priming, ect... as time went by I've learned a lot of my mistakes because at that time I was under the impression you throw in a coil and you just start vaping no wattage climb, no priming ect... lol (burnt hell)
But having a decent understanding on the whole vaping scene I will say it's still a Gamble when it comes to flavor with my crown tank 50% of the time I get a new coil and break it in that flavor is nowhere to be found in for the other 50% I get a new coil and the flavor is superb and just like you I tell people this and they have no idea what I'm talking about??? I do the same process with each coil i put in, and when it comes to breaking it in I start at 30 Watts and I go up by three digit increments instead of 5 I felt that work a lot better for me and as I'm climbing from 30 Watts. But I really do honestly believe it's because of the cotton and I've heard this from lots of people myself they packed that kind in so dense that sometimes I might not be putting enough in therefore giving me negative results as far as flavors concerned. I'm not somebody else likes to mess with coils and poke holes through I feel like it's b******* that you have to go through that extra work but let me tell you since I have been doing that I've been getting massive amounts of flavor with every coil!!!! which leads me to believe the problem you're having as was I is because the cotton is too dense and needs more juice in time to be saturated properly. And i will say to breaking in a coil plays a HUDGE!!!! factor....starting at low wattage, wattage climing, puff count ect...