While there is no question in my mind he's one of the top 3-4 Cyclones of all time, you can't hang it so quickly. The whole idea of hanging a jersey is that it's permanent and should never be taken lightly; it's a spot earned over time and given long after the excitement of the day has waned.
While it is clear that it should be hung when the time comes, it's disrespectful to the process to try and act on emotion rather than follow the tradition and meaning of the act. I hate most "traditions", but this is one that is necessary for many reasons.
That probably doesn't make a lot of sense (typing on my phone while in line), but the jist is that you don't enter Bryant into the NBA HOF the day he retires and circumvent the process, just like you don't hang an NCAA banner for Kentucky when they're 38-0, just like you don't hang Niang's jersey before he's fulfilled the overall requirements (i.e. graduating) and the dust has settled on his accomplishments.