The entire time I've been using the 6+. I could tell it needed the ram. Well I'm used to it and iOS 9 hasn't been too bad. I'll be getting the 7+ anyways.
By 2018 = 7+S should be really good with 256 GB and 4GB Ram.
and for a form factor it will be just the thickness of the 16 MP camera, nothing protruding, just that lens thickness
and no battery adios 12 will only use 128K of memory with the A19X chip.. 3D touch via your Apple watch