It depends on the amount of fields to be displayed here, but I think it’s important to show the complete information. This could potentially push the buttons outside the visible area and that’s not a good thing, maybe we should sticky them, put them before the metadata or make them collapsed inside a “Menu” button. I’ll need to give it some thought, but WDYT?
It’s a balancing act. Even when showing in landscape view we would waste space on something that’s not very useful. That’s why the “No Preview” element is very short. But I agree on the consistency issue, and it’s probably easier to implement too since we wouldn’t have one more case to code specific CSSs.
Good call, right now I don’t have it on my mockups, but I agree that it is an important feature.
Perhaps in the future we’ll have more features but for the initial versions it will be very simple, yes.
We could end up with an interface that’s very complex (main document + attachment preview). It’s an interesting take, and perhaps advanced users would like such complexity.
Something that’s comes to mind is that we had discussions in the past regarding a right sidebar. For now, we reserved this space for individual panels that the user might add there. Similar to XWiki Standard.