I used to like the Daydream clock function of Rootbox on the S2, whereby a dim clock is shown during Daydream mode (settings>display>daydream)
Samsung's daydream has all the other completely useless features (colours/photos) but no clock.
Typical bloody Sammy!
If you want the clock function however, then download DeskClock.apk and LockClock.apk from my DevHost site here
, (taken from 4.2.2 S2 RootBox) copy to /system/app set permissions to rw-r--r-- and reboot.
When you then go into the Daydream settings, you will get the far more useful clock option. I set this to come on when charging.