Pouncey is not a top 3 center but he's certainly in the 5-8 range. But he also just turned 25 years old and will be playing in a system tailor made for his skillset. His contract was given to him based off of what he is going to be, as well as what he's accomplished so far.
Pouncey is generally overrated. Or at least he used to be. He's been called overrated so much that he's pretty much underrated. To some fans, being overrated in anyway is like the worst possible thing a player can be. Guys like FlatsSteeler will hate them because they aren't the best at their position like some May claim them to be.