The Cs trade for Gasol and his outsized contract if they want to go all in on the last two years of KG's career. IF the Lakers would bite on Green, Lee and Bass for Gasol and Clark, and the Cs then sign a decent buyout vet to fill out the back of the rotation, they'd have a punchers' chance at the Finals again.
I don't see Bargnani and a half year rental of Calderon as much value for Gasol. At least with the Cs package you get three young athletic guys who can either take a role on the Lakers or be moved in the summer for better fitting pieces.
The way Pekovic is playing for the Wolves, they'd be crazy to move him for the aging, expensive Gasol. Atlanta is not trading Smith or Horford for him. Houston doesn't have any big contracts to match money with the Lakers even if they wanted Gasol still.
Bargnani is a better player by himself than Green, Lee, or Bass and he is a much better fit in the Lakers system. He is also pretty young and his contract isn't much different than Green's. Nash is hurt right now and will probably miss more time. Calderon is a pretty good backup and I certainly think the Lakers would consider re-signing him in the off season, to be the back-up/part time starter. I also think in Dantoni's system, Calderon and Nash could play together at times, especially with the league's penchant for playing smaller. You don't take on less talent because it fits better, especially when you are giving up a player as good as Gasol still is. It is just silly. Green, Lee, Bass is a horrible trade for the Lakers, now if Boston started adding assets like Sullinger, Bradley, draft picks, then the Lakers may bite, of course then it isn't worth it for Boston.
Pekovic is a good player, but he isn't good enough to get Minny over the hump, Gasol is. So Minnesota would absolutely trade Pekovic, Williams, and Barea for Gasol and that would leave them with a starting 5 of Gasol, Love, AK 47, Lee, and Rubio with Shved, Budinger, Roy, Ridnour, Howard, and Cunningham not to mention Stiemer and Amundson on the bench. That would be a top 4 team in the West and would pose a lot of problems for every single team in the league including Miami.