My 3 cents worth:
This situation is extremely difficult to fix.
Without a cross section penalty, in my view, the most logical design for a space fighter is a big flat sheet. As big as the core will allow. That sheet is completely covered in guns.
These ships might not look good either but without armour one would fire all guns and possibly turn side on to receive fire.
My point is if cross section penalties are removed ..... players will start complaining that all the fighters look like flat sheets.
Why is this issue so difficult to fix?
Well, lets use WW2 as an example. All of the planes, ships, tanks looked and operated in pretty much the same way. EG. all the tanks looked pretty much the same. Thats because, there is one best design. Now, yes, those designs changed over the course of the war but always in response to something. For example, larger guns and armour penetrating ammunition resulted in thicker and sloped armour. Better armour resulted in bigger guns and so on. My point is that at any one time, there is a best design. Given that in DU there are few economy/material/time constraints. Players will simply build that one best design every time.