Accurately representing the scene depicted on a series of covers over the years. I think for the old Marvel comics which had block colouring for some covers, the characters would be portrayed using their actual colors instead. Obviously the figures are not transformable or poseable. Which comic book cover would you like to see represented in 3D?
The first that immediately sprang to mine was UK #50, final part of the Dinobot Hunt storyline and a clash between Grimlock and Sludge. Google it. It would make a great piece! In a similar vein, UK #1 could also be impressive, and UK #79, 105 and 134. US #10 could be good.