Here's a novel idea. How about have tablets default to Start Screen and Metro mode and desktops and notebooks defaulting to looking just like Windows 7 - i.e. Start Menu and desktop mode? And having a user option to override that default.
Then the 0.001% of users who exclusively use Metro apps on their tablet would be happy and the rest of us could just ignore it completely. The only reason they're pushing Metro down everyone's throat is so that people write and use Metro apps and the Microsoft store has something to do.
As it is they've got the boat anchor that is Metro dragging down Windows 8 because people who like Windows 7 hate it. It's dragging down Windows RT too because no compelling Metro apps means that Windows RT is screwed. It's dragging down the Windows Store because no one actually wants Metro.
They've got one very unpopular product - Metro and a number of very popular ones - most notably Windows itself. They've tried to force the people that like and use Windows to use Metro. And probably the reason for that is because if Metro apps take off then so will Windows Phone. Which right now is tanking too.
However instead of this strategy making Metro and Windows Phone more popular they've actually managed to make desktop Windows less popular. PC sales are down and they've made Windows run much less well on non touchscreen machines but the tablets people are buying instead are running Android and iOS, not Windows.