There are a few BIG problems with casting auras on other people.
First is that pretty much kills any future hope for Rdm melee as any mage aura spells pretty much anchor us within the aura surrounding the mages.
Second is that these would pretty much essentially amount to cycles on crack. I mean if there's a limit of one per player then the party will likely demand that each player has one. You thought mindlessly spamming haste in a party was bad these would be 1000x times worse as I can't imagine a spell like this being quick to cast OR cheap on the MP.
I think one per player is way too many. I mean they would have to take into account that one job is giving 6 different "AoE" buffs. The buffs would have to be so saturated that they would be shadows of the originals which would kinda defeat the purpose of the idea.
If sphere type buffs were cast on other players there would need to be a great deal of restriction if they are to retain the full power of the normal spell.