With the lighting speed of the iPhone 6S Touch ID reader, there is more reason now than ever for the ability to turn on the display by touching it directly. I know some Androids have been doing this for awhile, I believe by double tapping on the display. I think the most obvious solution would be to 3D Touch "peek" to light up the display. If/when Apple removes the home button entirely and allows Touch ID to be implemented directly on the display then perhaps Apple would allow a 3D "peek" to light the display and a "pop" to unlock.