Yes! You have options for each thing. But it wont ask during install, only for location it will ask permission. You have to disable it manually in settings.
Universal Apps are better. Only problem i had till now is the design, most apps have the same look with same hamburger menu. I think that will be better as time passes because Universal Apps are pretty new right now.
I have a 640XL and its pretty smooth. But i prefer the Microsoft's facebook app because its better. I end up using the browser because it does not crash and all are there.
I think you better wait for Surface Pro 5. The kaby lake processors might be very powerful compared to current gen. I think even SP5 i3 will be way more powerful than SP3's i5.