The real reason Loki is evil: there is no pizza on Asgard. That poor deprived God had no idea that a better world was out there. One where he could be loved by the greasy, cheesy, over-toppinged triangles of love and goodness. And not die of a heart attack. Or get pimples from the grease. Instead of telling Thor that Odin was dead and attacking Jotunheim in Thor he would be sitting on the throne in his awesome helmet eating meat-lovers pizza and waving it in Volstaggs face. While Volstagg had drool dripping from his ginger beard. And instead of trying to take over Earth he would be reveling in the mischief of a Hawaiian pizza. So the world would be a better place. Or worse. Because, you know, Loki's not in it. And Loki makes EVERYTHING better. Even when he's trying to make it worse. He still makes it better by being there and looking THAT good.