A touch input metaphor and a pixel input metaphor not only should be, but MUST be, wholly different and wholly incompatible with one another. It’s not just that they do not comfortably co-exist within one form factor, it’s also that they do not comfortably co-exist within our minds eye.
In plain words, it’s no accident that the operating systems for tablets and notebooks are distinctly different from one another. On the contrary, their differences — their incompatibilities — are the essence of what makes them what they are.
I’ve been arguing that for a while now. The idea of having one GUI which works for both touch- and keyboard-based input is mired in so many complications that it’s implausible to succeed. However, I could imagine an operating system which changes its GUI to match the active input method.