Honestly I don't remember any way to pump up the static bonuses. The only thing I can recall is the Abjurant Champion prc from 3.5, and maybe the Argent Savant, 3.5 too. But in Pathfinder I couldn't recall any way to increase static bonuses that don't scale.
There were also a couple of greater versions of mage armor in 3.5, but nothing in PF.
If you use the Words of Power system (http://www.d20pfsrd.com/magic/variant-magic-rules/words-of-power) from UM then you do have some options. There's a third level effect word (Force Armor) which gives 4 + 1 for every four levels as an AC bonus, but only lasts 10 minutes per level. So it doesn't last as long, is two levels higher than mage armor, but does scale nicely per level. There's also one at sixth level, Force Ward, which givers 6 + 1 for every four levels.
If you are allowed to make use of the words of power, then you could take the Experimental Spellcaster feat, choose either Force Armor or Force Ward as your effect word. I'd personally go with Force Armor as a third level spell, Force Ward's spell level feels a bit to high to me for what it does. You've probably got more interesting stuff to cast with your sixth level spell slots.
Prerequisites: Ability to cast spells.Benefit: Select one class that grants you the ability to cast spells. You can now use the slots from that class to cast a limited number of words of power spells. Add all of the target words to your spell list and your spellbook, familiar, or list of spells known. In addition, add the boost meta word and one effect word of any level you can cast in the chosen class.
Special: You can take this feat multiple times. Each additional time you select this feat, add two effect or meta words to your spellbook, familiar, or list of spells known.
I feel it's a bit strange that these aren't just available as spells in some form too, it's a bit of a roundabout way to get access to improved versions of mage armor, but I guess it's better than nothing.
The miffic version mage armour is +6 and medium fortification.
What are you wearing on your arms? At a certain point, I usually give up on MA and head back to bracers as they go up to +8 (albeit it costs you an arm and a leg for that).
Would Empower metamagic bring it up?
Empower only works on variable numeric effects iirc
You could show your dm the 3.5 improved versions and ask to research a new spell based on them.
Greater mage armor from the 3.5 spell compendium is something i'd allow if a player wanted. 3rd level spell slots are pretty precious, if a caster wants to use one to make his AC 2 higher, I really dont see a reason not to allow it. It doesnt make sense that there is never a better version of mage armor, when its such a staple spell.
I think people alluded to it earlier, but specifically, Ascendant Spell would do it.
You have learned how to emulate mythic spells using non-mythic forces.
Benefit: You can modify a spell to imitate the mythic version of that spell. An ascendant spell uses the mythic version of the spell, but doesn't count as a mythic spell for the purposes of effects that interact with the spell, unless you are a mythic creature. You can't use the augmented version of the mythic spell, or use spells effects that require you to expend uses of mythic power (even if you have uses of mythic power available).
An ascendant spell uses up a spell slot 5 levels higher than the spell's actual level.
I'd say normally the +5 adjustment is too much to be worth it, but on something that you can cast long before battle and lasts all day? Could be nice.
Going from mage armor to bracers is one of the LAST things you do to raise AC, costwise...going from mage armor to +5 bracers is 25k in gold, and there are always more ways to grab +1 AC cheaper then that.
Indeed, on the table of +1 increases to armor, you use Mage Armor right up until Prot/Nat Armor +5, and you've a +6 Dex booster.
==Aelryinth
Behold! This is a great product and only costs $1. Bunches of options for Mage Armor.