Orton and Tebow are addressed indirectly by the "lots of bad things" that led off the sentence. Indefensible, and terrible but also separate from whether the right call was made on Cutler. Because if they are part of the conversation, so is Von Miller, Peyton Manning, and a Super Bowl title. Decisions have consequences, and almost all of McDaniels's decisions as head coach of the Broncos were bad.
However, he did make the right decision on Cutler - investing in him would have been a franchise killer. The Bears are proof. Cutler was not a guy to build around and McDaniels gets credit, however small, for recognizing it.
Cutler is significantly worse than Flacco & Stafford, both of whom have shown the ability to win and follow a team to the playoffs. Cutler proved he lacked "IT" and his teams suffered because of it.
As for what to do - do what McDaniels did and get the best trade return you can. Again, that he subsequently made terrible decisions with those picks is not the issue. (Though they really do matter when thinking McDaniels could someday be in charge in NE...but that's a totally different discussion). The act of recognizing and exorcising Smoking Jay Cutler was the right call.