My ideal scenario is to still bring Kyrie back with the max and get AD at all costs.
If it means dealing Smart, Brown and Tatum, that's fine
At least that will leave the team with defined roles.
Only issue here is to replace the 3 outgoing players, the Celts would probably have (gulp) re-sign Rozier and Morris.
I am not a big Rozier fan, but so be it.
We'd have 4 all-stars in our lineup in Kyrie, Hayward, Horford and Davis. Rozier would probably be the starting 2 guard unless
he doesn't mind coming off the bench and we pick-up a 2 guard with the MLE or the draft (or make another trade.)
Don't forget, it's not just the Celtics and Lakers that will be in on AD. The Knicks, Clippers, Rockets, Spurs, heck pretty much every team in the league could use a guy like AD on their team. Therefore, the Celts offer is going to have to be very competitive.
Also, I really don't think Kyrie would be as bad next year in the playoffs as he was this year. Sometimes, guys just have dud playoff performances. It sucks and comes at the wrong time, but it does happen. I doubt it happens 2 years in a row with someone as talented as Kyrie.