Stock.
Personally, I don't care about "fluff." I use my 10 as a tool, as my Icon and Bold 9930 before it. Everything needs to be quick and easily accessible. Long past are the days of NEEDING launchers to make phones usable and add missing features (Android Pre-K). In fact, the only change I have made to my device is the keyboard for increased efficiency.
Don't get me wrong, I appreciate people's desires to customize their phones, and in certain circumstances, replace poor stock launchers to remove clutter and improve usability. Fortunately, I think phones like the 10, the PRIV, and the MotoX PE have managed to keep the efficiency of stock (Google) android pretty well. I was pleased to have the option to have app folders and minimalist icons to keep things clean and simple. Good job HTC.
IMHO of course.
~Ex