I just really need to ask:
Solas is ****** Fen'Harel?
SOLAS IS ****** FEN'HAREL!?
GENIUS!
For one thing, it makes everything he says and does shine in a new light on a second playthrough.
For one, how he knows so much about how spirits and the Fade and Veil work, and how he has such an accurate memory of elven history, and a low opinion of the Dalish.
It also explains the more quirky, slightly off aspects about him. He knew about the orb when he didn't see it because he gave it to Corypheus and knew how to handle the Mark because he'd been handling the thing that created it for a very long time. More to the point, the bits about how he doesn't die when exploring ruins, and even that bit with Iron Bull about how he's the best self-taught fighter Bull's ever seen, can be explained perfectly if he IS, in fact, Fen'Harel. Half the stuff he's saying is bullshit that sounds believable; he doesn't fear getting eaten by giant spiders and has no kinks when he claims to be a self-taught mage because he's a f-ing GOD, and the only reason he's not taking full advantage of his powers is because he'd out himself as the accidental architect of the whole mess and would probably suffer through a very painful, awkward conversation with many people he respects.
I'd also like to say that if Solas is actually Fen'Harel, Bioware did a great job writing him, because he is in no way what you would expect a trickster god to be. And the fact that he can act not at all like a typical trickster god, yet it seems totally believable that that is what he is, given what we know about him and the trickster god he also is, is fantastic.
In fact...
Theory time:
If Solas is Fen'Harel, that'd mean he is the being who locked the Elven gods away from the Fade, but suppose he didn't mean to do this, or at least do it quite so permanently as it turned out to be. This could perhaps explain why he does not seem at all Trickster-God-y, and what he needed the orb for: he's not at his most jolly as a trickster god because he cut his fellows off from their people, and ruined both their lives (the lives of the gods and the elves) and his by mistakenly locking the gods away, so he's been searching for thousands of years for a way to undo his mistake. He thinks he's found it with the orb, but he can't get it to work properly, so he turns it over to Corypheus to get it jumpstarted, which just leads to more unintended, horrible shenanigans and pain for innocent people, the exact same thing that happened with the elves and his fellow gods. And when the orb is destroyed, he's just lost the one good chance he'd ever found at getting the other gods out of their prison; everything that happened with Corypheus, that he caused, can't even be given greater meaning in freeing the other gods as he meant to, and battling that incredible guilt and knowing he needs to pay for what he's done THIS time makes him leave the Inquisition as quickly as he can.