I am a tank guy, and I don't think you need more than 15-20w when you use RTA's. Personally, I am between 9 and 13w(depending on the juice) on a single coil Kayfun/Russian.
I have a couple of Pipeline Pros, one 18650 and one 18350, and they are really great. I've paired them up with Kayfun Lite+ V2 and a Russian 91%. The Russian 91% fits flush straight out of the box, since it has an adjustable centerpin, but on the Kayfun, I had to sand down the insulator about 1mm to get it to sit flush with no gap between that and the Pipeline. That was my main concern after watching reviews, as everyone of the reviewers complained about gaps.
I also like that the Pipeline is a short mod. It's exactly the same size as a Nemesis with a kick setup. You can also make the Pipeline Pro a little bit shorter if you go for the prolonged endcap, as it is less wasted space with that. It only makes the mod ~5mm longer with a one size larger battery.