For my personal use, battery life is OK as I am mobile quite a bit and have the ability to have it plugged in, so pretty much always fully charged. Know many, many people are satisfied with the both the new 6's, but I still prefer the size of my 5s.
As I know the path that Apple takes and understanding the need for IOS and hardware to be kept up to date, I believe that my 5s will max out within a couple of IOS upgrades and in order to take advantage of new tech, would need to upgrade hardware. I see nothing wrong with an additional sized phone in the line up. I don't need all the bells & whistles, so not having 3D Touch or Live Photos, for me, is not a show stopper.
For other content perusal,I have my iPad Air 2 and am very happy with it.