Link was a combination of a tad bit of his Brawl self, while being transitioned mostly to how he was in Melee. A good amount of his hitboxes are taken straight from Melee, and the rest was done from feedback from Melee players. (Such as Skler) He's gotten almost nothing but positive feedback from those who have played him, and the complaints are something we are not technically skilled enough to change, at the moment.
Our goal is to have Brawl characters transition seamlessly into the Melee environment. Part of those changes will consist of changing how Brawl exclusive characters play. We do not have an obligation to keep playstyles of specific characters from Brawl intact. However, we will do our best to make sure that they will play in a fun, competitive manner that fits into the "Melee feel." If you just want to play a Brawl character exactly how they are, go play Brawl - Project M isn't for you.