First of all, it's fascinating to see all the varying opinions on this.
My opinion: Ainge has positioned the team in such a way that at any given time—trade deadline, draft day, whenever—he can shift gears if the right opportunity presents itself.
He's made moves that have produced a consistently better team over the last few seasons, while at the same time collecting picks that should become (in one way or another) valuable players.
I've often been frustrated with Danny's holding pattern—pretty much every time he's "kicked the can down the road" at a trade deadline or on draft day—but I'm confident that he won't blink first when it comes to dealing with other teams.
So it's not really a matter of "do something" vs. "do nothing"; it's more like, "Danny WILL do something—the right thing—at the right time."