- dark mode
- customizable control center
- grouped notifications
- redesigned multitasking
- 3d touch widgets always on homescreen
- single sign on
- all apps are touch id protectable
- can turn on/off different types of notifications for every app
- redesigned app icons for the apple ones with the ugly white background
- more translucency and glass effects
- customizable/"redesigned" status bar
- redesigned sleeker volume level ui
- always show the widget screen if there are no notifications on the lock screen
- dark keyboard systemwide
- NEW WALLPAPER
- more and logical use of the new vibration engine
- app icon shadows with parallax effect
- redesigned ui for copy/paste bubbles
- "short-listen" mode for music app -> play every title of this album only 30/60 seconds (to quickly skip and listen to an album to spot any really great songs)
- Rich equalizer for systemwide sounds and equalizer settings in the now playing screen
- particular app downloads/installments -> you can choose which part of the app will be installed to save space, not installed but needed parts of an app could be downloaded later -> "cloud apps"
- a button to delete cached data (like the itunes store purchase a big movie trick)
- expanded icloud drive with a filesystem
- safari full download functionality
- mail app gets reading confirmations
- time controled messages
Some ideas
Edit: and i really would like to see some redesigned ui elements that were unchanged forever
- integrated brightness slider when playing videos like the volume slider