Google search clearing default launcher
This is a bug on the app, so whenever google now is turned on, the launcher gets clear and pressing the home button will make you choose a new launcher.
The issue came since Google launched GEL, and has not been fixed. I just want to put it visible to see if it can help others and also, if anyone has come up with a workaround. My only fix is to disable google search (or just clear all data).