Hi guys !
So I read your concept, and completely agree with the first point:
$background-color: #fff; is not possible for long term.
However, I see in your approach some flaws concerning DRY and reusable elements/modules like the ones we can see in OOCSS and similar libraries.
So I will point out what I think can be flaws, and my solutions, and would love your feedback on that: Context:
My page contains several blocks which all have the same background-color.
My page will evolved with time.