This muted flavor thing i heard it from some reviewers too, not trying to be a smart-... or anything since i consider myself an amateur in coil building business, but isnt the muted flavor supposed to be a wicking issue?
There are a bunch of variables which can impact to flavor. A few that come to mind are coil chamber size, coil location in relation to air intake, & tightness/looseness of draw. Wicking material can impact flavor, but if you use some good quality cotton and a couple rounds of wicking trial and error to determine whether the coil, atty &/or juice used likes to be wicked looser or tighter, once you find it, you'll wick it perfectly thereafter.
I think the issue with flavor on the Aqua is related to the airiness of draw and design, not the wicking. I built coils on it using cotton bacon which I wicked too loose initially causing it to wick too well & flood. After that I wrapped the cotton tighter and haven't had any more issues. In either case, the flavor wasn't as good as I'm used to. Personally, my only issues with it were the fact that the atty is too airy for me & the flavor doesn't come close to my squape. I haven't touched mine in weeks. I love the ease of filling it, the fact that it has 2 tank sizes and that it has a solid fixed center pin. The unique coil factor wasn't really a deterrent for me, just the airiness & "eh" flavor.