There are a lot of benefits to having a bigger screen. Websits with smaller fonts are easier to read.
I find myself reading books on the iPhone 6 ( I never use my iPad mini now, in fact i’ve lent it to a friend) reading books on the older iPhones seemed silly because you would be flicking through the pages almost a paragraph at a time, but there is a comfortable amount of text on each page.
The screen size is also much batter for drafting document on, on the older iPhones it can often feel like the keyboard is takimg up half the screen in notes or pages. Now you can read a good chunk of what you of what you have written above the keyboard.