Do we need lock screens?

Let's summarise the purposes of the lock screen on windows 8/rt and windows phone:

- providing the user a glance at time and date just by pressing the power button

- replacement for the missing notification centre to some degree (message counts, calendar entries, etc)

- providing the kind of personalisation that previously was provided by the desktop wallpaper: a large individually set wallpaper

Disadvantas of having a lock screen:

- it adds one more step to the process of getting started every time you use the device. Power button -> swipe up lock screen -> enter password/code (if you use one). I believe that the most effective and natural way of using a device (especially mobile devices) is to just pick it up and start doing the stuff you need to do, so that to me is the ideal goal.

So I wonder if there might be a way of fulfilling the purposes listed above without adding that (often annoying) gesture of unlocking the lock screen. Here are some ideas:

- Time/Date and notifications could easily be implemented at different places of the UI (notification centre, date/time on the start screen, etc) - that has been the subject of many forum discussions, so I won't go deeper into that. This solution would mean, that pressing the power button directly opens the start screen, which would in some way show the informations currently provided by the lock screen. The device would feel less personal because of the lack of a wallpaper.

- The process of getting started using the device could be reduced by one or two steps by using other gestures. For example, the waking up gesture (power button) and unlocking gesture (swiping up) could become one gesture (for example, swiping up an inch wakes the device up and shows the lock screen, swiping further up unlocks it).

- The lock screen could be reduced to a wallpaper plus time and date (with the notification functionality implemented in a separate notification centre plus live tiles), so the lock screen could unlock itself after a second, like a short welcome screen showing you time and date, and a personal wallpaper.

- My ideal vision of just picking up the device and immediately seeing the start screen without having to unlock or press anything would require some form of intelligent sensing by the phone, so it knows when I'm actually picking it up to use it. Any ideas? Eye tracking maybe? ;)