Hello,
First of all, no I do not want reputation to be availible on all your alts, so you just have to do it one time. I mean it more like an option. Let me explain.
I got around 35 reputation exalted on my hunter, and I really like to look at it and I feel quite proud. When I play on a alt, I just can't stand the fact that I have almost none reputations on exalted. So my question is, would it be a good idea that you can see your account wide reputations, but that you have to farm the reputation on your current character to unlock the rewards?