I'm not for big change during a tour and I don't expect England to change much for Melbourne. I would however be looking to make changes for May. Nasser is right. Cook inherited a team put together by Strauss and Flower. This should be seen as an exciting time for the captain to build a team for himself.
My thinking would be:
Openers
Cook stays, despite a few ex players suggesting that he should move down the order to take a bit of pressure off. He's a natural opener and should remain. I'd partner him up with Sam Robson. Strauss really rates him. He's got an excellent technique, and his stats have been good during the English domestic season, and on the EPP tour. I would avoid the temptation to move Root up as I think number 3 is the most difficult position in the batting order, and like Trott, I think he has the right temperament to do the job. He's also been moved about a lot, so an extended run in the same position will be good for him.
Middle order
Following Root at 3 I'd have Bell(best bat should always bat 4. Low enough to avoid the new ball, but high enough not to get stranded with the tail.) Stokes has to stay at 6 now. He's a quality batter. Just a bonus that he bowls relatively quick. Number 5 spot goes to Ballance. He has the most impressive stats and form in the county game behind him. I'm a fan of James Taylor and Jonny Bairstow also, so they wouldn't be too far away. Wouldn't completely close the door on Morgan or Bopara either.
Keeper
Buttler. Simple!
Spinner
Cupboard really is empty. Kerrigan is the only bowler in domestic cricket who is remotely dangerous. I would get him straight back in for the summer. Don't let him continually think about his debut, believing it could be years before they give him another chance. He'll only begin to doubt himself then.
Quicks
Very tempted to get rid of Anderson, as he's been useless for 7 tests. Although if you handed him the vice captaincy, and got his confidence up by letting him take few wickets against Sri Lanka on a green top, he could get himself back to somewhere near his best for the home matches against India, and then Australia the following year. Broad obviously joins him, which means we need someone quick to come in to complete the attack, as Broad and Anderson are just north of medium pace these days.
Mills, Wood and Overton are all quick, and in time I think Overton will be a real handful. But I would go back to Finn. He has shown signs of someone who can bowl at 90mph, and bowl magic balls. If someone can get hold of him before the summer and make him into what he was 18 months ago, I still believe he is the best young fast bowler in the land.
So team would be
Cook
Robson
Root
Bell
Ballance
Stokes
Buttler
Broad
Finn
Anderson
Kerrigan.