What I like about iOS is the complications are optional, my Grandma uses an iPad every day and doesn't need to learn the gestures or understand control centre etc.
3D Touch though I'm still skeptical about. I think its great and useful technology but I think Apple is struggling to implement it on top of an OS that never had it. If it was there from the start it I think it would feel completely necessary.
Like now when I want to move and remove apps I have to lightly hold down on an app icon, which doesn't really feel right considering I'm trying to 'dislodge' the apps so they can be moved, but if I touch it with too much force it will activate 3D Touch.
There also is no clue as to which buttons or apps can be 3D touched, maybe if they had some kind of special glow or tiny clue this would be nicer to use. A UI interface that requires trial and error might struggle to take off.
Having said this I think they've made a really good job of it, I just wonder if a bit more time spent deeply considering its implementation would have been useful here.