Thankfully we can kind of swap back to a Windows 8.1 style startmenu, though they moved a lot of stuff for no reason other then to appease the people who refuse to move beyond the yeolde startmenu. The lack of windows borders and shadow highlighting is beyond irritating its a minor usability thing but even all of the Linux DE that ditched window borders kept the shadow highlighting. The ability to actually sure gestures on multi monitor is really the only possible reason i could see upgrading on my work desktop.
Things that would be nice and could be in there would be on domain attached Win10 machines not to have every new user do that were getting things ready for you dialog it makes Win8.1 as a lab machine operating system kinda irritating.
Other minor things that would be nice as features to have but Microsoft refuses to give to us. SFTP and SSH support, I mean come on from an enterprise level the fact I can't do the bulk of my job without installing putty or cygwin when just about every other operating system supports this by default.
The white interface flat theme i get a lot of OS are doing but i can't stop thinking it reminds me of Gnome3 in Fedora.
Hopefully Win10 is a bit more usable on tablets, if so then I would prefer it as Win8.1 can still be pretty irritating on the surface tablets.
Still dislike that Microsoft ditched what is easily a better interface Win8.1 start screen (yes even for desktops if you would actually use it you would get why) just because people complained. I get wanting to make changes to the interface but it seems like every single change in Win10 that replaced a gesture or something I was used to in Win8.1 takes extra clicks.
Going to use it because the multi monitor features drive me up a wall that windows has lacked that so many Linux DE have had forever.
Something I will have to test at work is supposedly by default Remote Desktop Services can support OpenGL meaning we can finally install the CAD applications remotely because they do a stupid check for OpenGL support when installed and because when you RDP in it swaps to a software render without support it freaks out. Very small use case but something that would be nice at work.
I prefer my Win8.1 user interface on my desktop but some other advantages might prompt me to swap at work. At home the new driver model for AMD drivers has a lot less CPU overhead and other things meaning Dx11 runs quite a bit faster I have been running modified drivers to get it but now i can run official drivers so that's why I am upgrading at home.
Edit: Appears window shadows are rendering now after they have not all day so what the hell Microsoft.