Welcome to the ProVarinati!
Carto tanks were were my go to attachments for a very long time. I never tried dual coils, based on the advice of those I trusted (primarily Baditude) that they can use up more juice and the possibility of one coil burning out before the other. From what I read, the flavor/performance of dual coils (if it is actually better) isn't enough over single coils to justify the hassle. (YMMV)
Since they are essentially all made the same, it's interesting that brands can taste noticeably different. I tended to use Smok (called Smoktech by many vendors, but they are the same) most of the time since I liked flanged and Boge didn't come in flanged (they may now, I don't know). I have one tank I used Boge in, but they didn't come prepunched (which they do now), so the vendor punched them for me. I like high pg juice, so that didn't work very well. I need the tiny laser punched holes or got flooding.
IKenVape was always out of stock, so I didn't get to try them for a long time. When I finally did, I found that I liked Platinum more than Fusion, even though Platinum didn't have a flange. There was some reason the Fusion didn't stay wet enough for me and I was always filling it up. I have some IKV Nitros around somewhere, but I haven't opened them. By the time I got them I was already on to a different type of set up. The Nitros I got were single coil, which I actually bought by accident. I was curious about the unfilled Nitros, but it turns out they only come in dual coil. It the only time I wanted to try dual coil.
Anyway, my point is there are so many different kinds to try, that it can take some experimenting to find what you like.