Perfect. I hope it is included in the design, even if it doesn't get used for anything official, another hackable feature that will probably never be used but still might be one day.If something like I²C is used, you don't need any more wires on the ribbon. MIPI already has an I²C interface.
That's not an alternative, e-ink is better for your eyes because it is not shining light constantly into your eyes. (which is what LCD does)It makes more sense to just go out of the sunlight and use the actual screen