I don't want to discount how valuable this may be to you. However, for the average sysadmin, or developer who spends time in shells on many different machines,

I don't want to discount how valuable this may be to you. However, for the average sysadmin, or developer who spends time in shells on many different machines, I would gently suggest that this is not a good idea. It's not a significant enough improvement over the way it works out-of-the-box to merit both (1) not getting used to Ctrl-r and (2) getting used to a different behavior for the arrow keys. Just my opinion, of course.