I primarily MTL but some setups I use (like the Siren V2 with airholes open) I'm usually doing more of a restricted lung hit. I like both types of vaping and have some VERY restricted MTL setups and some more open ones. I like the variety.
I'd say, look for tanks that suit what you like now... e.g. if you have a setup that you like to run at a certain wattage and it's more "MTL" design, then you know you are wanting setups that are kind of "crossover" depending on airflow and type of coil you build.
I've found myself surprised to "enjoy" certain setups a great deal that I didn't think I'd like. Like a fixed wattage setup that has a lowest option of 30 watts. That's more than double my usual style of vaping, but with a 0.8 coil, a different driptip, and restricting airflow, I find I enjoyed that setup a great deal, although it was at much "higher" wattage than I usually use. I enjoy it first thing in the morning, when I really want to get some nicotine in me, etc.
I don't think the labels are so important, what is important is finding vapes you like,, and then moving forward, buying vapes that fall somewhere in that wheelhouse. Over time, you'll get things narrowed down. I'm glad I didn't restrict myself to a specific draw or wattage, as the tanks I have are fairly eclectic for a MTL vaper, although I rarely am using resistances below 0.7. I really can't do MAJOR sub0hm setups, it's way too much vape for me. But mainly, just experiment. I got a few setups I hated along the way, but was able to give them away, and part of successful vaping is being able to experiment with stuff until you have a collection of things you like.
I just won a smokstick setup and I will be interested in trying it (and prepared to neither hate or love it, until I see how I can get it to perform. I doubt it will fit my "style" but if it doesn't, someone will benefit from it, down the line...
Anna