This sounds more like Immortal controlled than automated, and honestly I'm tired of the amount of Immortal controlled stuff that already exists, I don't think this needs it. If I misunderstood, please explain more precisely what you think the requirements are to earn shield/aura/barrier.

It would be automated. SHield at 30, Aura 35, Barrier 42

To get SHield to trigger, you would need meet the following criteria.
a) Have accumulated 'battle-time' to justify the need to gain protective mana control while in battle. It would work like a shifter form mastery (At rank 30 you would begin to feel more at ease with mana during battle. Similar to how shifters go through form useage to CONFIDENT). Therefor mages that actually are fighting mobs, leveling, and taking part in war would benefit quicker than a mage that sits at the inn roleplaying about the rabbits. PK fighting would count double, to encourage Player vs Player fighting. (Maybe have something to prevent same ethos/cabal/ power practicers who will exploit this with a friend.) ALignment opposites and opposing cabals...Not sure how to fix neutrals from power practicing...might need some tweaking.
b) Edge points, exploration points, imm-xp, ect. could expediate the process slightly. Instead of having to put in 20 hours of battle for example, once you hit a certain tier of mastery, you would shave off some hours. This would encourage exploration and roleplay.
c)Age of character. It would also shave off some of the mana protection requirements.

In theory this idea would automate the process. It would reward players that are fighting, exploring, roleplaying(for imm-xp) bumps. The geek gatherers like myself can still do their searching and exploration. (I personally don't usually enter the PK scene until I have completed all my gathering, equipment allocation, etc) The people that hate the current system are the types that want action and want to see results for their effort. They would gain the spells probably just as fast as the slow/boring gatherer, but be fighting and participating to get there.

Lets be honest, once a mage has found his sleeks. THere is no reason why they cannot use wands constantly for every situation, as long as they devote a cool off period to regather each log in. Heck, I usually would carry 4-5 barriers, and 3-4 of each aura/shield. You get to a point that you always are ABSed.

The 'Warmage' approach would even the playing field for the balls to the wall fighting type chars.

As all mages gain in age/knowledge/experience/ they will become more powerfull. Put some timers in place for each type.