The bigger problem is you need operating system support. Linux/android has it. iOS has it. If iOS has it there’s a very good chance that macOS has it (we’ll probably find out on Tuesday).
What does Windows support heterogeneous cores at all? I don’t think it does. And until that happens, would you be able to sell a chip to the public?
Surface ARM laptops have big.little so there must be some kind of support but I don't have any confidence that it's good. It will take MS a while to get it refined. People are probably better off disabling the little cores so threads don't slow down by getting accidentally scheduled on them.
This isn't possible. The cores are already as fast as they can be, so moving from 10 big to 1 big would only reduce performance.