WatchOS 3 has the benefit of a year or so of actual user data behind it, and it shows. Apple had ideas about how people might or should use the watch, and now it’s tweaking those ideas based on things that people are actually doing.
I like, but have been underwhelmed by, my watch. I’m hopeful this can fix a large portion of the issues. Remapping the side button is a big improvement; it’s basically worthless right now. It’s also frustrating that there are not more complications, and that complications that should be useful—like MLB AtBat—rarely work or update quickly enough.