All of what you say is true. It is a short term fix, with an identifiable ceiling. Thing is, once you go there, and start recruiting to it, it is very hard to shift away from. OL are not traditional (i.e. gigantic persons, not very mobile, built to rock back on their heels and manhandle pass rushers), a bunch of smallish shifty WR, and a couple of scatback RB's. QB is definitely easier to manage since some very average passers end up being stars. Not many of those players go on to the NFL, which means you are recruiting, and living and dying, on guys who are somewhat outliers at their positions. Look at where Leach has been, TT, WSU and now Miss. St. They remain Air Raid based teams. It is sort of like herpes apparently, once you get it, it doesn't go away. There are other offenses that offer a little more flexibility and could be just as useful to the Buffs.
EDIT: plus if CU went Air Raid, what do we do with the 17 TE's CU has recruited?