My iPhone 7 Plus had increased performance after updating to iOS 11.1 for several hours, nearly back to where it was under 10.3.3 (could unlock lock screen with a single home press), before reverting back to the somewhat pokey iOS 11 performance.
The orientation bug wasn’t fixed on my iPad Air 2. Actually it is now worse. Previously launching a landscape only app while in portrait or a portrait only app while in landscape sometimes got the orientation stuck until I completely flipped the iPad around. Today after updating to iOS 11.1, for the first time the orientation got completely stuck. I eventually managed to unstick it by toggling orientation lock off and on several times and locking and unlocking the screen several times. I haven’t had to do that since iOS 10.2.
I was also experiencing this on my Air 2 with all 11.0.x, but on 11.1 it hasn’t happened yet!