Without saying whether I'd be either for or against trying to acquire these other two guys, let's look at potential deals that would work, see how palatable it would be for both Minnesota and New York, and then look below at how the Celtics could fill out the roster with solid MLE or vet min players to compliment their new star triumvirate.
For the sake of discussion, let's assume that the Celtics pick falls in the 4-6 range and the ATL/BKN pick falls in the 15-17 range.
For Minnesota, is #5/#16/Sullinger/Clippers 2015 #1 enough to get their attention?
For NY, is Green/Bass (exp)/Bogans (fully un-guaranteed)/Nets 2016, 2018 & Right to swap w/them in 2017 enough?
Obviously this cashes in pretty much all of our prime chips but that could be Ainge's preference instead of rolling the dice on the draft and so many young guys. Celtics would still have their own picks each year to find other role players, and would have the MLE/vet min to add a defensive-minded center & shooting guard (Bradley is gone in this scenario because they can't pay everyone), which would be very important. We've already seen how much easier it is to find solid role players once you have a contending core in place, though, so it could be done.
How would the roster look after this?
PG: Rondo
SG: FA (see below)
SF: C. Anthony
PF: Love
C: Faverani or FA (see below)
Existing bench:
Olynyk
Wallace
Faverani
J. Anthony
Reasonable defensive-minded SG FAs:
Sefolosha/S. Brown (Not much depth here so they may have to explore minor trades to fill the SG role. I'm ignoring FAs like Ray Allen (obviously!

), Nick Young and Vince Carter because they are all defensive liabilities.
Reasonable C FAs (again, thinking defense):
Gortat (would MLE be enough?)/Okafor/Oden/Lavoy Allen
As for the other backups, this summer's market is flooded with potentially cheap veteran point guards & small forwards so neither should be hard positions to fill.
FA PGs:
Stuckey/Chalmers/M.Williams/Livingston/Sessions/Hinrich/D.Harris
FA SFs:
Marion/Pierce(would love to see him retire here a champion)/Kirilenko/Granger/Ariza/C.Butler/Battier/M.Williams/R.Jefferson
Anyway, thanks for reading (whoever does

).