If the Protanks are enjoyable and working for you, why be bothered with looking for something else?
Some folks are content with what they have, others crave more. It's nothing to be ashamed about or feeling like a failure over.
I like warm vapor, and so I stick with my T2s, iclears and the Phoenix rebuildable atomizer. I read that genesis style atomizers are a cooler vape unless one gets a reducer for the top cap. I'm interested in the Fogger V2,
kayfun Lite, etc... but I try to read a lot, research to measure the vape quality... and never hesistate to ask on the forum how the vape is (warm/cold).
If those 2 weren't right for you, it might just be the coil resistance of the build, which can be adjusted when you build it yourself. An RSST and Nimbus are only as good as the build. Try out a cheap
rda like the Mini-RDA or Phoenix v4 -- less than $10 and build yourself a 2 ohm coil and see how it goes.