I haven’t been that impressed with Carr, but maybe the addition of a back like Bush will take some of the pressure off him. Personally, I would shop Carr and sign Young (yes, pass on Bush and Leinert). That would keep him in Texas, boosting fan support and keeping the seats filled.
The Texans should trade the draft pick for offensive linemen. Dominick Davis is a pretty good RB, and they are going to find that out when he does to another team and makes the Pro Bowl with them.
Carr's a good QB when he gets time to throw the ball. They should shop the first pick to get on offensive line, no QB and no RB will ever succeed behind the OL. Ploys like grabbing Young only keep the seats filled for a year or two, eventually the local fans get tired of watching your team destroy this hometown favorite's career.