Underrated:
Blastoise (Coolest design ever!)
Emboar (Gets too much hate.)
Scolipede (Next to Excadrill, was my main lead in Pokemon Black. People don't like him cause of his typing.)
Early Gen Rodents (Raticate, Bibarel, and Watchog all have a certain charm to them. Raticate has those adorably tiny arms, Bibarel has that really cute face with wide eyes, a red nose, and buck teeth, and Watchog has a cool psychopathic look, plus huge puffy cheeks.)
Overrated:
Garchomp (Now that too many fours isn't here to tell me I'm not allowed to hate this piece of ****, I can complain about how much I hate Garchomp.)
Serperior (Pound for pound, he's TEN times uglier than Emboar. Why is he so popular?)
Scizor (Personality wise, it has about as much as a piece of wood.)
Gallade (I know this guy's an UU Pokemon, but he has a cult following him. Most people see a badass character with personality and elbow blades. I see... a stick figure. ...Yeah, a glorified stick figure. Really awesome. ...Really.)
Bibarel. It's awesome with Thunder + Charge Beam + Surf + Curse. But everyone uses it like a HM slave..
Bibarel will ALWAYS be more than an HM slave to me.