iOS 11 is not a "refinement" imo. On the iPad, yes iOS is way better for multitasking but, otherwise, I'm very disappointed as well. Notifications on iOS 10 is still ugly to me, but not only they didn't fix that fir 11, but they expand the ugly thing on the lock screen if you listen music.
The lock screen integration when you simply want to see your notifications on the home screen feels weird and not intuitive at all to me.
The only thing that appeal to me is the new features for the music app, and the multitasking on the iPad and its pretty much all I can say that I like.
Smart invert colors was a great surprise and consolation of not having a true dark mode at first, but when you realize Safari still shows the picture inverted, you know this new setting is not as useful as you first thought