Overrated? That's a shoe-in: John Gotti. He might also be a contender for douchiest boss of all time. Everything about the guy screamed douche nozzle.
I'd throw in Nicky Scarfo as well. Obviously an extremely dangerous guy, but way too bloodthirsty for his own good especially in regards to the other crime groups in the area as well as the guys from his own family.
That's going a bit far. I think Gotti was very respected and feared, even liked. He was just not fit to be a boss in a time when LE was all out to get the mob, and had been after him even before he was boss.
