Not Matthews, but I'd see if I could get a sign and trade for Parsons, perhaps. Parsons would be a great fit in the Triangle and type of offense we do. Good bench guy.
Gasol/O'Quinn/Hernangomez
Porzingis/Thomas
Melo/Parsons
Afflalo/Lee
Grant/Galloway/Calderon
That team is about 10 wins better than this one, at the very least. You could also play really smaller quicker highly skilled lineups like Porzingis or Gasol at 5, Melo at 4, Parsons at 3, Galloway at 2 and Calderon or Grant at 1.
Think we should look at it from outside the box - look at good fits with the most talent as opposed to the generic "positional" basketball needs. Yes Conley, Batum or DeRozan all make sense to a degree, but tons of teams are after them and they'll get huge offers. We may not be in position to get any of them. So instead of paying players who have been career 5th options or backups - starter money - we go out and make our strengths (front court) even stronger with Gasol/Parsons, improve our effectiveness in the Triangle/offense, and hope that with some development from Grant, less minute load on Afflalo (by signing a guy like Lee) we don't run into the same issues we're seeing this year. With Gasol we'll have a legit post up option, with Parsons a really good triple threat player who can fill in when Melo is hurt, and there's some realistic hope that Porzingis can elevate into a better scorer next year.
I'd pursue Batum, DeRozan and Conley (and flirt with Durant obviously, knowing he's likely not coming) - and also touch base with Pau Gasol and Dwight Howard. Both guys are major league talent, despite being in their 30's. Making your strengths even stronger isn't a bad thing. Even if your weaknesses don't improve as much, instead of being a team that can score 100 a night (on average) you're now capable to score 103 or 104. That's going to help as well. Just upgrade, period. Doesn't have to be at the weaker positions even tough obvious where we need the most help is at SG/PG.