Although I haven't played with this much myself, I've been told the metered connection option only exists on Wifi connections. The option isn't available for ethernet connections.
MS: "Sorry, Eastern Europe." ?
As I am on Windows 10 Home, I speak with experience. You can delay the installation with the option Settings > Update & security > Advanced options > Notify to schedule restart. You'll be notified to schedule a restart, which is when it'll install the updates it automatically downloaded.
I haven't tested it in great detail, but I think that only controls when the restart happens, not when the updates are actually installed. More than once I've gone into the updates window on a Win10 Home laptop to see that it wanted to reboot and was saying it would restart at 3:15 AM with an option to defer, but it looked like the updates it was rebooting for had already been installed.
Also, not all updates require a reboot, even in Win7 and 8.
One other thing I noticed is that Win10 Home completely removes support for connecting to a WSUS server.
My control group for that was a Win8.1 Pro desktop and a Win8.1 Home laptop, both of which were configured through Group Policy to get their updates from a WSUS server, therefore they only see updates that I have approved.
After upgrading them both to Win10 with no other changes, the Pro machine still only shows updates approved through WSUS (and it hilariously shows up as "Windows Vista" in the WSUS management console now). The Win10 Home machine no longer updates its status in WSUS and seems to be getting updates directly from Microsoft, ignoring the policy settings entirely.