Hi. I used to be an Apple-devices' lover once. But I had the same experience as you did. Apple has more restrictions than Android, making it kinda safe- but boring at the same time. I got my device jailbroken and realized that, it was the worst thing to do! Firstly it was a void of contract (You can always switch back from a jailbreak software), it made my device exposed to vulnerable security flaws and my device lost its charge faster than ever. But the advantage? You could download paid apps for free and customize your device the way you always wanted, but for after paying a heavy price.
However, now I think that Android phones are better than that of Apple's in many ways- there is a huge variety of choice, there is great hardware, screens, resolution, camera and what not? There are like a 100 reasons why Android phones are better than Apple.
As you've mentioned that you want an Android phone (Samsung Galaxy S7 specifically) but not willing to shed money on a device that lags or never receives update, I recommend you to read this article which lists the some common S7 problems and shows the way to solve them:
10 Common Galaxy S7 Problems & How to Fix Them.
There are many other phones running on Android, that can last you the next 3 years. All depends on your budget. The One Plus 3 is a great $400 dollars phone. If you want something high-end and filled with the latest technology- you can buy the Samsung Galaxy Note 7 for a staggering $900. Oh, just to remind you, Android Central is running a giveaway- where if you're lucky enough, you can win a Note 7. I've linked the URL below.
https://gleam.io/P1TrN/win-a-note-7-...-galaxy-note-7
Hope that helps!