I don't think addons can do this sort of thing for you you have to switch aspects yourself. What I think could be done is maybe a addon that notifies you when your mana gets to 15% and to switch AotV on and at 75% to turn on another aspect. I would love to know how someone gets on with this as I sometimes have trouble myself with forgetting to turn on AotV when mana is low.
(had to put one in this post lol)