My hope is he can keep working hard and maintain a great diet (he does seem to admire Tom Brady's regime and longevity).
If he Keeps it up, it should be a no brainer for Ainge to re-sign him and we have a premium scorer on a championship team (hopefully with some help as well).
I don't think his 30 PPG will last after this season and his 4th quarter magic won't entirely last either, but even if he's 25 PPG kind of guy who can hit some clutch shots in the 4th, perfectly fine.