It's not a secret that the Miami Dolphins need a franchise quarterback. They have needed one since 1999 and it's evident as they have had the most starting quarterbacks in the NFL since then—from Jay Fiedler to A.J. Feeley and from Chad Pennington to Chad Henne. The Dolphins have been the laughingstock of the league at the position and should be looking to upgrade sooner rather than later.
It was thought that the acquisition of Brandon Marshall would take the Dolphins' passing game to the next level even without an elite quarterback at the helm, but it simply hasn't happened. Marshall has underachieved in his two years with the Dolphins and has even brought up the question of trading him to get some value while still possible.
I completely disagree with the Dolphins even having a thought about trading Marshall because he has the potential to be an elite receiver. Many fans, including myself, were impressed and surprised with his performance in the pro bowl. That's the Brandon Marshall Dolphins fans were hoping to see when the organization traded for him.
Lately, the talk of the town has been about how Brandon Marshall would be the top receiver in the league with an elite quarterback, like the ones in the pro bowl, throwing him the ball. What some fans know but simply refuse to accept is that defenses in the pro bowl are playing at an effort of about 25 percent. Sure Marshall has the ability to be a top receiver, but it won't be because of the quarterback; it will be because of him.
Keep in mind that he dropped 12 passes this year and a few of them would have been touchdowns. He has all the physical tools to be elite, but his mind has to want it as well. Marshall also took his vacation time to open the eyes of say, Jeff Ireland when he said:
“Down in Miami, getting a feel for different quarterbacks, had three or four of them throughout my two years there, Quarterbacks make it easier for me. These guys are putting it in the right places and I’m making plays. It’s easy right now.”
There's no question Matt Moore is not the long-term answer in Miami, but don't think for a second that Marshall's performance in the pro bowl will transform into the regular season next year. There are many factors playing into this like the team's new offensive scheme (which will definitely help the passing game), the team's ability to run the ball and other receivers that step up. In the pro bowl, you have no pressure on the quarterback and have quality receivers lined up on every down. Marshall is constantly getting double-teamed and should be able to deal with that. 
A quarterback will help Brandon Marshall and the offense develop into a more potent offense, but his performance in the pro bowl, as incredible as it was, will not dictate and is by no indication a preview of how Marshall will play in the regular season.