First of all, I'd like to hear the opinion of other people who have most of the faction in existance on exalted on exactly. Personally I'm only missing Shado Pan Assault and Ogrila for that matter.
I remember people asking for this, one of the argument was that it would remove a big time sink and people would run out of things to do faster. Personally I think this is a very bad argument in case of old reputations. Yes there are some people who might do old reputatons (pre Pandaria) twice but they are most likely a tiny minority.
In all honesty, how many people do you think would do Ravenholdt, The Steamwheedle Cartel or Ogrila twice? The vast majority of people don't even do them once!
Another important point are removed factions such as the Zandalari and Shendralar. They apparently still do count for the character who got them, but don't for new ones and arent achievable anymore. Thus when switching mains people are put at a disadvantage.
What is your opinion on this matter, should OLD and only OLD reputations as in pre Pandaria or even pre Cataclysm be account wide since they don't give an actual advantage and are purely cosmetic by now. If yes, why do you think they should and if you're opposed to it why shouldn't they?