Everything I'm hearing on the rumor mill says that the 2nd overall pick is not sufficient to get an all-star.
All-defensive NBA players may not be all-stars, but their on-court impact is pretty similar or just less than an all-star level player. Most advanced stats bear this out and most contenders in the NBA know the value of all-defensive players.
I don't think we'd have to include the 14 and the 30 in that trade. Smart is on a great contract for a couple more years, fits securely into the Iggy trade exception this year, and can fill the Iggy/Livingston role at a high level. His havoc-style offensive and defensive game would fit perfect in their system.
I think the Warriors would do a trade of Smart for 2, or maybe Smart and 30 for 2.
I don't think the Celtics would, unless they really, really believed in the 2nd pick. Like, Ainge would have to be convinced like he was with Tatum to do that trade.