You forgot On/Off vs. Volume button placement (opposite sides means you often press the wrong one).
The RAM, we will have to see. For now it seems fine on my Plus. 2 iOS versions down the road I think it could be problematic.
The 6 Plus is too slippery to hold bare. Thus, it needs a case anyway, which makes the protruding camera issue moot.
Antenna bands, likewise will be covered up with the required case.
Bezels, I guess could be a little smaller on the top and bottom. On the sides I think they are OK because of the edge swipe gestures, and again, the fact that a case needs to curl around a bit (and still allow for edge gesturing).
I can't speak to battery life on the 6, but on the 6 Plus it's fantastic.
Waterproofing would be nice. I'm not really sure of what adding requires technically. Is Apple just lazy, or is there a real engineering reason why it couldn't be done?