In keeping with the recent "go post it on the wands thread" stuff from gameplay, specifically regarding the post about how paladins, healers and shamans get sanctuary...

Give all mages a built-in dam redux spell that scales in effectiveness as they increase in rank.

They get the spell at rank 20. At that rank it provides approximately half the benefit shield or aura do now. On the order of 10% dam reduction.

At rank 35 it's like shield or aura.

At rank 45 it's like barrier is now.

Give it a decent sized cool down timer. Maybe the duration is six hours but you have to wait a full twelve (or more) before you can use it again. The goal here is to force people to use it tactically, as opposed to a healer or paladin who can keep sanctuary up almost indefinitely.

Get rid of all barrier wands, sleek or otherwise.

Modify aura/shield such that each is half as effective when the mage is affected by this new spell. This effectively reduces the "high end" of damage reduction that mages can currently achieve. Which makes sense since we're now giving them "barrier on a stick".

On the other hand, it also retains the motivation to explore/etc., since having sleek amber/sienna on hand allows you to account for those times when you're prevented from using your built-in spell (e.g. when it just wore off).

Key points:

1. "Power up" to the "base" mage, sans preps.

2. "Power down" to the "optimal" mage, e.g. a+s+b.

3. Inability to keep built-in spell up 24/7 so encourages tactical use.

4. Retains current "exploration/knowledge" benefit, but the magnitude of that benefit is reduced.