Primary function of my Apple Watch (Sport) is telling time at a glance. For that reason, despite trying several different watch faces, I keep coming back to the Utility analog face. It's easy to read at the quickest of glances, even in bright sunlight here in the desert southwest. My previous daily ticker was a Rolex Air King, which I still have in a desk drawer. I wore that for 15 years. I keep it in case someday I decide to go back to the simple, pure, automatic mechanical watch.
While the Apple Watch is not the "always-on clock" of a mechanical watch, it's pretty close... probably 98% of the occasions I look at it for the time, it's already showing the watch face. 2% of the time I might have my wrist at a strange angle while holding a coffee cup or something and can't tilt it conveniently to check the time.
I frequently use the activity tracking, notifications, screen / answer phone calls / voicemails, read important emails from people on my VIP list, reply to texts, set timers using Siri, check the outside temperature (surprisingly accurate), and stay mindful of any upcoming conference calls and tasks. My phone stays on my desk most of the time. The Watch is also my bedside clock and occasional alarm clock. Oh... and yes, Apple Pay is just neat on the Watch. I use that whenever I can.
However, as much as I like my Apple Watch, I realize it isn't for everyone, and neither is the iPhone itself. Some people are best off without, or with a much simpler single-tasking device... or perhaps one of the Android offerings. Nothing wrong with a flip-phone and a regular watch. The world continues to spin. That we have these amazing choices in the first place is really pretty neat.