I have to fully agree. Although iOS 9 wasn't that bad since I've had an iPhone 6s, I think iOS 10 does bring the needed optimizations. It's a pretty major difference, even on the iPhone 6s. Slightly quicker opening of apps and folders, less stuttering, no stutters at all after reboot when opening an app, folder, Spotlight, Control Center of Notification Center. That happened to much with iOS 9.
I love iOS 10 already. Been using it from beta 1 on my main device. Most people wouldn't take that risk, but I've done that since iOS 5 beta. Even iOS 8 on the iPhone 4s, which by the way was the worst experience I've ever had. But I never regret taking risks to try out new features. Especially now with iOS 10. It feels like a stable release. Not just with beta 6/7, but even with beta 3/4 already. There were some crashes, but most of the stutters were gone already, and apps launched quick enough.
They finally show the real Apple here. I hope it's not just for now, but that they will make iOS 11 such a great release as well. Believe me, this will attract more customers. I know people who actually replaced their iPhone by an Android phone because of those issues every time and lack of good features. Then I told them iOS 10, and showed them the best features. Some of them are already looking forward to the next iPhone, just because of iOS 10. I think that does say something, doesn't it?