Ok, ok, so a brief toss of thoughts - naturally I may be completely wrong and while I'm mostly versed in the lore involved, remembering it all isn't my strength. I really like some of the theories that I've seen here, such as the Dwarves/Titans stuff, it all makes a lot of sense to me.
As I was catching up, though, a few thoughts grabbed me, I'm not sure anyone has brought it up yet (or if I'm even remotely right):
1. Mythal as a human. I didn't drink from the well, so all I know about that part is from what you guys have posted here, and it might be just that I'm going on a single screenshot, BUT is it significant that there seem to be two people in supposed-Mythal? I mean, her outline is overlapped and not with a perfect fit, the noses aren't right for one. This may be just a fade-in/fade-out effect that I'm missing because I didn't actually see it play out visually. If that is significant and I'm not just grasping at straws, it would make sense to me that it could be a representation of Mythal "reborn" as Andraste and possibly reborn again as Flemeth (she does have a thing for helping humans and about serving justice - that would fit with Andraste, so my theory is that basically every time a god has an "incarnation" or joining with an existing soul, s/he becomes more than what they each were individually, i.e. Asha'bellanar is deeply involved with the plight of the elves without actually interfering in their lives, yet she goes out of her way to help potential heroes and bringers of justice). Andraste was all about justice, was she not? It would make sense that Mythal is "reborn" as her, a perfect way to serve her purpose after her godly betrayal. This is including justice for the elves, also, and that fits her profile - she was betrayed, which also fits the story of being betrayed several times, but more importantly, Andraste was human, which gives us more reason to suspect this than simply Flemeth being human. (Why choose another human vessel? Why would Flemeth the original person care about people beyond herself? She didn't strike me as the justice-seeking type on a grander scale. Plus, let us not forget Andraste's bestowing of the sword of justice... passing on the torch?) Who can say whether she actually believed in the Maker or that was Mythal's way of guiding people into a semblance of unity, a kind of last-ditch attempt to prevent humans, elves and dwarves from totally destroying each other? (Remember, it turns out the Elvhen were already at one another's throats long before Tevinter entered the picture. Everything was already falling apart.) Flemeth, too, was always ambiguous about her reasons for helping our heroes along, implying that she has a greater grand scheme of things and what we attribute to her as evil (Morrigan's perspective) or good (her final reunion with Morrigan) are simply indicative that she has greater things to worry about than trifles such as what's right and what's wrong. If I have my lore correctly, by Andraste's time the Elvhen gods were already sealed away, so her ability to help her people would be severely limited without allies, which brings me to the next point.
2. Solas and his "denial" about the gods being gods. My question is this - how would a god look upon himself? From his perspective, he is just a being and his equals are nothing special. To him, they are not gods. Does that actually mean that from a mortal (or immortal elven) perspective he is not a god? Not necessarily. See, we only get Fen'Harel's perspective, by his own admission he's something akin to the god of rebellion - is it not utterly rebellious to disabuse worshippers and bid them not to pray to their gods? He robs the people of this chance, and his reasons are murky at best. I believe from what I've seen in Solas that he did mean well and did mess up royally and now is willing to pay the price for it. I really am all for the suggestions that he's like the paragon of a wisdom/pride spirit (he keeps going on about that in particular, wisdom spirits and Lavellan's "wisdom" which I always thought curious as my Lavellan's actions didn't exactly strike me as... wise at the time) but I'd hold off on the theory that he's "simply" a very ancient, immortal elf with abilities above and beyond "regular immortal" elves. If he is that close to being a spirit, he also has an inhuman (pardon the expression) control over how he interacts with the Fade. He was also very, very suggestive of a time when the Fade was in a kind of symbiosis with the world, there was a permanent, open gate between them if they were not infused completely - *gasp* what if this was his plan, to recreate that? Only the world was waaay too different, the minds of the mortals in Thedas are no longer able to approach the Fade without destroying themselves and everyone else? *ponders furiously* I add to this that I support the notion that Fen'Harel basically missed the entire destruction of Arlathan because he was asleep - only now does he see the true consequences of his actions, plus he gave the orb to Corypheus waaaay before the here and now.
3. Lavellan as something special. We know Cole's and Solas' references to Lavellan as something beyond "merely" another elf - "burning too brightly" and all that. I'm going on these pieces: first, the theory that the Old Gods are actually Elvhen Gods or a part of their essence at least in corrupted form; second, going by our Thedas history that 4 blights went down before DA:O where Old Gods were destroyed, i.e. the pantheon is no longer complete; third, there is a reference (sorry, I forget where I read it, but I believe it was in-game lore) that spirits actually go to the Fade, not to some "beyond," or at least, they don't go there immediately. This is like Wheel of Time if anyone reads it, the Heroes of the Horn who wander Tel'aran'rhiod; basically is it not theoretically possible that Lavellan is the reborn form of one of those dead gods....? Bear with me. We know that gods who possess a body already inhabited by a spirit hear voices. Kieran was created through ritual while the Old God was still very much alive in the dragon's body. Flemeth is an infusion of Mythal and her original self, BUT she is obviously at least somewhat two distinct entities. Solas is more integrated than that, if he ever truly was separate, but then I would remind everyone of the bits of lore that point to Fen'Harel being either formless or possibly interpretable as a shapeshifter - i.e. he has no need to possess a living body if he somehow managed to create/keep an original elven body. So what happens to the gods that die? Why should my Lavellan be special other than accidentally gaining the mark? Why would a god for Maker's sake be so drawn to me, especially considering his less-than-enthusiastic opinion about modern elves in general? (Not that I'm complaining.)
4. OK, this one is less a theory and more a question: I know my heart at least was slightly trampled into feeble shreds when Abelas basically dismissed me as being basically the same as the shems - yet not Solas. He said something like "Elvhen like you..." why did that not totally LEAP out at my Lavellan?? Because just a second ago Lavellan herself was nowhere near possessing the honor of being even near "like them" - also, is it not suspicious to her that Solas seems to be pretty much fluent in the ancient elven tongue...? I'm a linguist, and I know that just knowing phrases, knowing words is nowhere near enough to be able to speak it fluently, and with so many scattered remnants being the only guide, it's no wonder that no elf today actually speaks it - so how can Solas? I mean, we know, but why did Lavellan not give him slant-eyes at it I wonder? (I could just say she was so madly in love with him from the start that she didn't really want to dig where she might find answers she doesn't want to hear. But I rebel at this notion. He must have infected me with his godly ways of rebellion.)
Ok, all of this is basically random brainstorming on my part and possibly a lot of it can be refuted on the spot, but judging by what I've read so far here in the theories (magnificent, by the way, you all are ridiculously awesome!) I think I am right on at least some of these points. *cough* And maybe I'll just shut up now.........