This happens on pretty much every device that supports metal. No such control center issues exist on the iPhone 5. Yes, the iPhone 5 is smoother than the iPhone 6S with control center. I have both devices, I've used them side by side. The 6S is perfectly fine sometimes, but other times it is very noticeable. Same deal with my iPhone 6, but it is much worse usually. Tapping on the airdrop button has more apparent issues if you still can't see it. Sometimes it's smooth on the 6S, sometimes it isn't. It always is on the 5 though. Control center is perfect on iPhone 5 when used over the lock screen, home screen, open folder, and the app switcher (if you aren't looking just at the home screen card) but all of those scenarios are bad on iPhone 6 and they choke up a bit at times on the 6S.
This is about control center performance on the home and lock screens by the way, the iPhone 5 chokes up with the airdrop menu when control center is used in different areas, for example, over a keyboard or open folder. It isn't perfect, but it's much better.
Also I've noticed that the control centers look a little different across devices. iPhone 5S and higher I think has translucent buttons and sliders, iPhone 5 does not.
First and second photos are screenshots from an iPhone 6, standard and zoomed mode. Control center performs generally the same. The last screenshot is from an iPhone 5. Notice the lack of translucent buttons and sliders. Disabled buttons are colored lighter as well