I use what works best for me. I personally love the pixel launcher, the Google now swipe to the left is useful and I actually like the rounded icons. I actually had Nova prime on my s7e and used all the pixel launcher enhancements on Nova lol
I have a gear s2 and find that Textra works best with notifications to my watch. I also think it's the best third party messaging app. It is very smooth and snappy.
I feel like using the stock experience that the pixel gives is the best way to use the phone. It's just so buttery smooth, I have yet to have a stutter or hiccup like I always had on the s7e.