I would consider this trade if Danny knows now that he's not going to be able to or not going to want to resign big baby and perk after this season.
I think Baby is in for a big raise. I'd personally love to keep him, but who knows what kind of crazy offer someone might throw at him. Same with Perk. Again, I most likely wouldn't do this trade, but I mean Melo is an amazing talent, a top 5 talent in the League IMO, and getting him next to Rondo for the long run would be amazing. We would be set for the next decade if he would sign an extension. Even if he wouldn't sign an extension, Danny might feel confident that once he's here in Boston he'd want to resign.
Melo is big enough to play the 4, especially against the main teams in the east we are concerned with. He can go against Bosh and Turkoglu. And he can go against Odom.
We could take Shelden back in the trade and he and Semeh could be our 4th and 5th big men. Danny would have to find a 3rd big between now and April though. Sheed?
Rondo
Ray
Paul
Melo
KG
Dwest
Wafer
Keys
Sheed/Shelden/Luke
Shaq/ Semeh + whatever Danny can find. We know players always get cut at trade deadline.
We could also start KG and Shaq and have either Ray or Melo come off the bench in a Manu role. Again, it doesn't matter who starts, it matters who finishes and since Shaq can't really play in crunch time, Melo takes Big Baby's role closing the game out with the big 4. Ray could come off the bench and still play 30 min. Or Melo could. As long as he gets his 30+ and is on the court for the final 6 min of the game, I'm sure it would be okay with either of them.
We know once the playoffs come around, the rotation gets shorter since Melo and Rondo can play 40+ min each and Paul, Ray, and KG can play 35+. Our bench could be Dwest, Keys filling out the backup PG and wing positions. Then Shaq, Sheed, Semeh, Shelden, or another big backing up the 4,5.
I love this team and think as constructed we'll almost definitely win the championship, so a major shakeup is highly highly unlikely. But this may be Danny's best chance to land a Superstar with Rondo.
And remember, we've been playing this year without JO and Perk. So basically it's the team we've had on the floor this season, minus Baby and Nate, but plus Melo, Shelden, and maybe Sheed.