A few things after reading this thread.
1. A QB's success, any QB's success is entirely dependant on the other players around him. If the O-line is not keeping the D off of him he has no chance to set up, read the D, step into, and make his pass following through. Last year with the O-line resembling a MASH unit we had no consistency and the QB's started each snap in panic mode, "get rid of the ball before I get killed" mode. This season with a deeper, more experienced O-line we should see a different look on O regardless of who the QB is. This same O-line will also make the running game more consistently effective further helping the QB's. If the recievers can step up and make some big catches that for the most part they did not make last year, the few chances they had to complete a pattern, the O should be very much improved.
2. Height of the QB can make a difference for an offense but not all the difference. First off a lot of posters here have made a big deal out of the idea that Miller is 6'8", Solder 6'7", Givens 6'6" etc. This would be significant if O-linemen played standing straight up but they don't. Pass blocking effectively involves raising slightly on your toes but playing in a position that involves bent knees and a bend at the waist leaning slightly forward to absorb the forward momentum of the defender. Because of this the lineman is going to be a few inches below his standing height. The D linemen are going to be leaning forward as well so the effective height that a QB has to see over is not that high. That said the further away from the QB the line can maintain their position the easier it is for the QB to see and the wider the lanes between defenders to see and pass through. Also a consideration is how effectively an OL can keep the DL from getting hands up into the passing lanes.
There have been a number of very effective QBs who are not much taller than Cody. Drew Brees is only about an inch to an inch and a half taller and does pretty well. On the other hand the majority of NFL QBs are 6'3" to 6'6" so there is clearly and advantage.
3. Hawk loves his kid but is also highly competitive and not dumb. He is going to play the QB that he thinks is going to give him the best chance to win. Despite his shortcomings (pun intended) Cody is not a bad option. He is not Sam Bradford, he is not Tim Tebow, but he is a decent Big XII quality QB. If Hansen steps up in the mental parts of the game he is clearly more gifted than Cody. As a Buffs fan I would love to see this happen because Hansen gives us more of a deep ball threat and his mobility adds significant problems for a D. He showed significant moxie stepping in as a true freshman behind a badly broken line. If he can develop an understanding of enough of the O to be effective I don't question that Hawk will truly consider handing him the reins.
4. Ballinger is a big, mobile, athletic player. He also seems to be reasonably intelligent as a FB player. Unfortunately we have all seen that talent doesn't always translate to production on the field. I would like to have him around as added depth at QB but realistically unless he made some real steps forward he was not going to see the field short a major disaster, in that case I would rather have his scholly and use on of the Fr. as a disaster QB. I wish him the best in his future whether it is as a QB at a smaller school or in BB. Realistically, this kind of thing happens. Players see that their future is not where they wanted to go. If he wants to blame it on Cody being Hawk's son or anything else it happens. Future recruits are going to see that Cody is now a JR. No matter what happens he only has one year after this one so that will not be an issue. If Hansen ends up as the starter, Cody is no longer a factor for recruits.
5. It is amazing that coachs tend to be geniuses when they have healthy talent and idiots when they lack it. Helfrich will be looked at very different if we are averaging close to 5 yards a carry in the running game and completing passes on third down because the QBs are not running for their lives. With a healthy DS knocking LBs on their butts and D-coordinators afraid of Speedy turning hand-offs into TDs there will be room and opportunity for the passing game to succeed.
I am not saying that this year we should be U$C or need extra digits on the scoreboard but I am expecting a major step forward this year. Hopefully this takes some of the pressure off of the D as well. We are going bowling, I don't know where but barring a bus wreck on the way to the stadium we will win a number more games than last year.