I am not saying I like this but I could see a Porzingis + Burke or Ntilikina for Smart and Al.
Why for Boston, the deal gives the Cs the 3rd scorer that they need and adds brings better spacing to the court. A lineup of Pritchard, Brown, Tatum, Grant and KP really would open things up for Tatum and Brown. It also opens up minutes for the young guys with the departure of Smart.
Why not for Boston, they makes the team much softer. KP has never proven that he can stay healthy or play winning basketball. I also would worry how KP handles being the "3rd guy"
Why for Dallas, Smart makes alot of sense next to Luka he compliments his game very well and brings defense and toughness to the back-court. This deal also rids the Mavs of KPs contract. AL will fit nicely with the pieces they have and this is a core that could make some noise in the playoffs.
Why not for Dallas, I'm not sure they can move KP with Smart coming back as the big addition.