Isn't it just as likely that the Maker, if "he" exists at all, is simply another god-like entity amidst a pantheon of other god-like entities (from the Old Gods, to the elven gods, etc etc etc) -- all of whom may be no more than very powerful Spirits and/or magically imbued creatures? I think there's a strong inclination by some fans to attribute to the Maker and the Chantry a RL religious allegory that perhaps the writers never intended. Sure, are there correlations? Of course... people draw from existing ideas all the time. But I don't think the writers of the DA series intended, oh, a C.S. Lewis approach when coming up with the Maker and the Chantry.
The existence of the Black City in the Fade is no proof at all that the Chantry has anything right: Not when spirits like Justice in Awakening openly speak of how so much of the Fade is purely a construct of the dreams and thoughts spirits witness in the minds of sleeping mortals. An emulation, an attempt to fill their own world with the imaginative creations they can only experience passively [unless they manage to breach the veil].
Add to it that Andraste came after the First Blight: And if I'm correct up until that point there was no mention of a Maker, yes? Andraste - and then her followers - come up with their allegories and tenants concerning the Maker, but where the root idea of this Deity comes from, we - as players - have no idea (unless I've missed something! Which is totally and utterly possible!). Did the Tevinters teach of a Primary Deity, some force of Creation? The Elven Pantheon has All-Father/All-Mother type representations: Was Andraste influenced by these ideas during her time as a slave to the Tevinters, either from the Imperium itself or elven slaves around her? And given Andraste arriving after the devastation of the First Blight - which in and of itself lasted hundreds of years - are we really going to look to Chantry writings (themselves writing a good deal after Andraste was martyred) to provide the definitive (or, worse, literal) interpretation of what happened to cause the Blights, Darkspawn, Archdemons, etc?
Since I don't, personally, believe Bioware was setting out to teach RL religious allegory in any Lewis-ian manner or Philosophy/Ideology of any sort, I think it's far more likely that either:
a) It'll turn out that the Maker is nothing more than a spirit/ideal/embodiment-- either unique unto itself or a reflection of some other established pantheon.

We'll simply.... never know. Because it isn't important to the game that we know.
Meh... just my rambles, written before having my second cup of coffee, so if this makes no sense, my pardons: I blame the nasty overload of blood in my caffeine-stream. ⌐.⌐