Wow, that's on by default? Damn, I had to limit my internet activity last month and ended with less than 2GB to spare in my data cap.
Definitely not touching Windows 10 again.
Hahah yeah it's like torrenting for the OS (peer to peer update sharing). It's a way for MS to cheap out on as much data fees as possible I guess.
Anyway, if you don't game on PC, skipping W10 isn't the end of the world. Windows on the back end really hasn't changed since Vista in any gigantic way.
That said, I would still recommend learning how to tweak W10 to work like you want it to and getting it before too long (before the free entry year is up). The reasons are how Microsoft supports it's OSes, especially in regards to forced obsolescence and security.
For example, although there is nothing fundamentally wrong with a fully updated Windows Vista or 7, Microsoft has already locked them out from even DirectX 11.1, and Windows 8/8.1 is locked out from DirectX 12. Also, security updates and support for things like .net, activeX, etc are going to drop out much sooner on the older OSes.
And some intro tips on fixing up Win10 :
In addition to that, I'd recommend getting CCleaner and tweaking your startup settings to reduce clutter/overhead. I would recommend Classic Shell over Start8 though. I have W10 on my HTPC, Gaming PC, Work Laptop, and Ultrabook, and they all work flawlessly.