I'd be inclined myself to purchase a "true" MTL tank and try vaping higher nicotine at much lower wattage, and see if you prefer it. You can put a MTL tank on the mod you have, you will just get much better battery life.
Some good, higher resistance tanks include the Nautilus 2 (comes with a 1.8 coil for a more restricted hit, and a 0.7 coil which is a bit more cloudy, and you'd likely run that coil at slightly higher wattage. If the heat and volume of vapor is making you cough, then a MTL tank is likely going to be easier to manage (at first, and it may become your preference anyway.) Other good starter tanks include the Ijoy elf tank which takes Nautlius 2 coils and does a slightly better job on flavor, capacity and ease of topfilling. You could try a Kabuki tank (I would start with a clone at Fasttech first if you do that, as the originals are very expensive). Great flavor, also takes the N2 coils, but slightly larger capacity. Flavor machine, but bottom fill (although, easy bottom fill). Could also look at an Ego One Mega tank, only don't use the coils provided, you would want to buy separately a box of Joytech CLR coils (I would start with the 1.0 ones, although there is also a 0.5 coil if you want slightly more clouds). Great flavor though, and good longevity of coils, that are also really easy to rewick and refill, so they are cost effective as well.
Best of luck,
Anna