I think you have to judge each on their value to the team in their respective eras, then look at comparing them to each other, as well as how they rank in the league. Starr was a coach on the field and able to carry out Lombardi's vision for several years, and helped mold the team into a powerhouse. He was a top-three QB, but probably not THE top QB (I like Johnny U there). Favre was tough as nails (until that cold January day in 2007) with an arm like a howitzer. At his prime, he was the epitome of a leader who carried the team and made everyone better. Rodgers is probably smarter than almost any other player to wear the green-and-gold and his physical gifts are way above average.
Yet, I keep going back to Hutson, who on film looks like he could step into the locker room today and start. Rodgers would love to have him running routes! But the thing that seals it for me is Hutson's ability to play offense and defense. Hutson was without parallel as a split end and was also a talented safety who once led the league in interceptions (1940). He was miles ahead of other receivers during his era and helped create the modern receiver route, and then he'd flip sides and stop the other team's players -- he was great on both sides of the ball.
That makes Hutson without parallel and the greatest Packer to suit up (IMHO). 