I think I also would say that they need to keep the home button and put a light around it for notifications (assignable colors by function). I don't much care about the headphone jack because me and ear buds do NOT get along (small ears). The hardware for me is fine. Just keep improving the software with new customization features. I've used all the other OS's out there (Windows Phone, Android and Blackberry) and they each have something to offer. Do not over complicate this. They do need to do better with missed notifications and maybe the more customization ability but, and I never thought I'd say this, iOS doesn't need to get overly crazy with changes. One simple thing I can think of? - how about putting the temp on the weather icon? In other words, a simplified version of Windows live tiles.
P.S. The Galaxy S7 screen is phenomenal. I could go for that.