Dematteis did some neat stuff with Electro where he was basically a nobody with a lot of resentment towards the world who basically used the powers he got to make money and lash out at the world.
I always just figured Herman was the kind of guy that would be robbing people even if he wasn't a supervillain. He's basically a goon-for-hire and bankrobber by trade.
Don't get me wrong. I love a complex, sympathetic villain as much as anybody, but I kind of like that those two guys were just kind of dicks who did what they did for money and power. I feel like there would definitely be guys like that in a world filled with super powers. Some would be conflicted or mentally ill or misguided, but some of them would just be super-jerks, right? I kind of like that contrast to the Osborns and Eddie Brocks of the world.