If you really miss these functions you might be able to get them back by trying out a launcher (see this forum wiki post).
I personally use a way differently designed launcher but there should be several ones that allow you to choose which of your āscreensā will be the one you get to when pressing the āHomeā button so you can have screens to the left of your homescreen.
Some launchers are very powerful and might even be able to adjust things like the background image values and provide you with a customizable lockscreen. It does not hurt to try them out - I tested about 20 in the past and all of them were as easy to remove like any other app.
Iām also very happy to now have Marshmallow with all its nice features on my phone