I don't think LA is going to let some combination of Ingram, Ball, Kuzma, etc. get in the way of getting AD a year earlier. If AD rejects his extension, it's game on for Magic and he's going to close the deal. The Celtics can beat whatever LA offers but Tatum is the trump card in any bidding war. Is Ainge going to risk Tatum if AD seems to want LA? He didn't seem too interested in even offering up Jaylen for Kawhi. That was probably because he's always had his eyes on AD so maybe his approach is different this time.
A package of Jaylen + won't be getting it done this summer because LA can and will top that. This is going to be tough for Ainge to navigate since all his 2019 picks will need to be made before we know what AD is going to do on his extension unless he publicly says something beforehand.
What I was getting at is that I think the Knicks and Clippers are dark horse candidates in the Unibrower sweepstakes at the moment, but if Davis says Lakers or bust, they might stay out of the bidding.
I'm not sure that Boston does have a huge problem beating out the Lakers because I don't think very much of Kuzma (seriously, he couldn't defend Kobe to a room full of Laker fans), and think that Ingram is far closer to a poor man's DeRozan than a future star (at least Brown's upside is poor man's Jimmy Butler, which is a much better player). Ball would be the crown jewel, I'm not sure that he fits all that well with Ingram (to be brutally frank he'd be a much better fit with a transition player like Brown), and his upside, I think, is third star.
Boston always has the option of moving Hayward to a third team to accumulate more talent for the offer (say to the Pacers for Myles Turner and a pick or Utah for Exum/filler/Utah's late lottery pick). You can build a contender around Irving and Davis with Morris returning to play the 4, Tatum the 3, and Smart/2019 lottery wing (since you
know that's going to happen) to plump the rotation.