This is a space vessel... not a derelict sea vessel that's about to sink to the bottom of the ocean from years of neglect. ;)
Looks like an old tin-can that would implode if space-dust even grazed the SHIELD.
Edit: And wouldn't it take eons for something to rust out in space... if even at all? Doesn't make sense for a space vessel to be so heavily rusted unless they literally raided to terrestrial junkyard to bolt the thing together and that was the original condition of the parts. IMHO, remove the rust COMPLETELY and give it burn scars and dents (battle damage) to show that its weathered many a mine-field and backwoods trade routes through asteroid fields and exploding gas pockets.
Just as we reap the golden wheat, must we also cut free of the chains! [eS]