There is no GLOOM like the gloom that is DOOM. I love his ennui and for so many other reasons. His look is iconic and has never changed after all these decades. When his first toys were made the only note the toy company gave Marvel was to change Doom's look - 'too Medieval' they said like it was a bad thing to be the greatest looking bad guy ever. It's too bad his own ego will never allow him to conquer the universe despite his ability to do that very thing. He can care about someone else but that is a rare person indeed. Valeria Richards calls him Grandfather as a term of respect and admiration - something that humbles Doom - Destroyer of World. I hope that with the loss of the Fantastic Four to Marvel's comic line-up that the company can find someplace to stick the Ruler of Latveria.
You can see the only times when DOOM's iconic look was changed. Once for his Secret Wars figure (the one that was created because the toy guys thought he looked too medieval) and for the first Fantastic Four movie.