Just fron what I've read.
Windows 10:
- better peformance (quicker boot time and such)
- updates do not constantly get notified in ur face like win 7
- notification system windows 10 pretty neat
-gaming peformance very similar but win 10 has support for direct x 12
- loads of little things like search bar can show news and tons of extras (which can be nice if you tweak it the way you like, but also very frustrating if u don't want all that extra crap)
So to me apart from the design win 10 is a far better operating system