Suggestion: Aura interaction for blue!

Ok I brought it up in another thread but I beilve it could actually get its own post. After some more thinking on it my suggestion is that you change so when you activate another aura it only gives global cooldown to auras and not all of our spells. Often you have a resistance aura, devoution or sanctity on when fighting players and would love to be able switching for Concentration when it gets heated for a safe heal or do a reliable Hammer of Wrath and then switch back to original aura.

As it is now that is more or less impossible considering the speed in fights and would make your Holy Light be a 4 sec cast (counting in latency) which probably makes it a even longer cast then using same aura all the time. That is one example there is others where you fight warlocks or mages and you see they change spell casting by look on glowing hands in times like that you want to switch fast without taking up time to not be able cast a seal do HoJ or a simple heal.

Blizzard have stated long ago they wanted to change the aura interactivity by players so it isent one aura up all the time that more or less never get changed.

I think this suggestion would be a good way to make people change aura more often. By keeping the global cooldown between auras (so you cant change it superfast) will make it balanced and not overpowered.