I've been reviewing Lia. Overall looks good and I am ready to approve her pending ML's review. I did not a couple of issues. The biggest is that both Riftwarden Orphan and Arcane Temper provide Trait bonuses to concentration checks. Those will not stack. They do provide other benefits so you need not change them, but you'll only get the larger +2 bonus from Riftwarden Orphan.
Given the nature of the adventure you really should pick a deity.
Have a name and gender for your familiar?
You don't list CMB (+2 I believe) or CMD (15 I believe).
You haven't taken so much a dagger for martial combat. Is that intentional or have you just not finished shopping yet?
A description would be good.
Now the good stuff. I like the background!
You may add 5 permanent hp and +2 to any skill. Please add the following to your Riftwarden Orphan trait:
Riftwarden Orphan (Archmage): The PC gains a +4 trait bonus on caster level checks to penetrate a demon's spell resistance. Once per day, she can recharge a charged magic item by expending one use of mythic power. Doing so adds a number of charges equal to 1d10 + her mythic tier to the item, up to its normal maximum number of charges.
Might want to use some of your remaining cash for a wand...
Oh and as Shayuri mentioned earlier, mage armor and bracers of armor both provide an armor bonus and thus do not stack. An amulet of natural armor will stack, but of course it costs more.