I would like to see the ultimate universe take some D-list villains and make them more interesting:
Ultimate Trapster:
Instead of a guy with a glue gun, I think ultimate Trapster should be a guy obessed with death traps (think of an Ultimate Marvel version of the Jigsaw Killer) . Either he can he a merc who specailizes in using traps to extract information from his victims or he is just a sadist with a lot of time and money on his hands. Unlike the 616 Trapster, who is prone to fits of anger and easily loses control, the Ultimate version of Peter Petruski is very much in control, almost always calm and cool. He doesn't wear a costume, perfering a business suit or perhaps jeans, jacket and plan shirt. Petruski enjoys the sense of control he has over his victims, he can even enjoy a glass of wine while tormenting his vicitms.
Ultimate Egghead:
Dr. Elihas Starr, was once of the top scientists at SHIELD, however, soon he was displaced by Hank Pym and Bruce Banner. He also got very little respect at work, with the other staff nick naming him "Egghead" because of his bookish nature and bald head (his head isn't shaped like a egg in the Ultimate Universe). Tired of the lack of respect he got at SHIELD, Dr. Starr decided to sell SHIELD secrets to the highest bidder, secretly sending out plans for top secret technoloy to any criminal or terrorist, in exchange for a huge sum of money wired into his Swiss bank account.