I did the exact same thing. The G4 camera was good, but the S7 Edge camera is better IMO in terms of color. It's great with low lighting... And how often do you really need 16 over 12mp pics? Me? Rarely. I'm glad with the change.
Not sure if this thread is dead or what, but I followed instructions exactly, phone came back up perfectly, but NONE of my old apps that I had before are there... ideas?