Surface book pro concept

This is just an idea I've been chewing on:

Imagine a Surface Pro that you can use with an ordinary type cover or with a keyboard dock similar to the Surface Book.

The keyboard dock could include extra I/O, GPU, battery (essential), and speakers maybe, just to be impressive. 

It could run a little ribbon cable to a flat connector under the kickstand, since it will need PCI lanes.

You could even choose between keyboard docks: One of them could include space for a 2.5 inch storage drive, but that's just me. Some could include extra RAM for running VMs.

Essentially, it should be able to be a completely portable tablet and also an ultrabook replacement.