I'm not even trading DG for Bridges straight up. Much less with JA in the deal.
If you're wanting to compete for a championship and Bridges is your first or second option, you're in trouble. At 27, he is what he is at this point in his career, which is a high end 3&D wing without the play-making abilities other more complete wings have.
Meanwhile, DG is 23, and just came off a season averaging 22 points, 8 assists, and shooting 41% from three. I read somewhere he was only 1-2 point guards in the NBA with those numbers.