Bingowings said:
To illustrate this point I put Vaderious' interior shot roughly in scale into the window slit of this quite close shot of the head (bear in mind it hasn't been adjusted for shade and it hasn't got window glass and the interior shot is still too big).

You can hardly see a thing.

I would still prefer something like the above than nothing at all. ANYTHING to show that this is not just a model with nothing in it.

Sevb32:
It being a viewscreen would be a cool idea too, but even then that would justify a bluish window or something other than a black bar.