Introduce an AA which, when clicked, allows the caster to cast a group buff spell to create a 'Buff Aura'. This aura, which stays active for a certain amount of time, allows players to run through it to get their buffs. All the buffing classes cast their buff aura in a spot and people who need buffs simply run through it. This could help ease the lag pile issues, as well as improve buffing classes' quality of life in groups and raids.
I think the main lag effect of Auras is that every time a PC/NPC (including swarm pets) moves, they are checked if they are in or out of the range of every aura in the zone, which also may be continually moving. The Shaman Pact of the Wolf aura, with it's apparently unlimited range may be avoiding that, maybe all player auras should be made unlimited range to cut CPU cycles.
That may be the case but not sure how that would work for aura's that are not limited to group members.
I'm not sure how this is better than Mass Group Buff or Tranquil Blessing. I also don't see why it is necessary when Tranquil Blessing works great . . . except for the synchronization issue where your client says it is in out of combat mode but Tranquil Blessing says you are not.
Auras would negate the need to recast for a period of time. Think of it like the AE heal auras priests can place anywhere. Place a buff aura down and move on.
Those heal auras don't last that long so you would end up recasting the aura instead of just recasting the buff.
I don't think they would want long lasting aura's up in zones all that random players can run through to get buffs. They do intend for buffs to be recast from time to time otherwise they would just make them permanent as they intend for them to be recast from time to time especially after a death as they can make buffs last through death as well. If you really want to reduce the buffing strain I would ask fro them to last longer first.
As I am sure a large portion of the player base would be, the devs however don't seem to be okay with that as they have extended buff duration but not made the permanent.