Challenge accepted. I'll start also include immersion, PC and antagonists since they're all connected.
Thanks! Here are my counterpoints:
Your first point is that Origins clearly demonstrates why the Blight has to be stopped. This is true, though it's also true in Inquisition. In Hushed Whispers and Champions of the Just both demonstrate why Corypheus has to be stopped, and they do so by cleverly implementing the "show don't tell" guideline. It's bleak to see your companions fallen, corrupted by red lyrium or, in Leliana's case, the Blight. I'm also a fan of the game over screen text during those missions which outline the direct consequences of your failure. The key here is that you actually experience how crappy the world would be if Corypheus wins. It outlines both the totality of his victory and the stakes quite clearly, and it was a good choice to personalize your failure by centering the horror of a Corypheus failure on the bodies of your companions (this is also why it's false to say Inquisition keeps the darkness at a distance, but more on that later). Meanwhile, in Origins, you never see what happens to Lothering and it takes a DLC to see the effects of Ostagar. The most effective section of the game is the Deep Roads with the Broodmother for this reason: it's not just that the Blight is a threat, but that you are actually shown the specifics of the apocalypse and what will happen. Inquisition works similarly.
Speaking of showing the effects, it's simply not true that Inquisition doesn't show dark stuff or the consequences of war. What exactly am I missing about burning villages, slaughtered civilians, mass pits of dead that have risen to become undead, abominations taking over mansions and refugees, rogue bands of templars and mages killing and plundering, deserters from Orlesian armies doing the same in places like Emerald Graves, Red Templars kidnapping people and implanting red lyrium inside them to the point that one begs you to kill her? What, because it wasn't a cutscene? What about couples trying to flee bandits and being killed, a mother trying to protect her child by throwing herself on top of it before a sword through the chest kills them both? Because it's environmental storytelling, it doesn't exist? What about Cassandra's Seeker plotline and meeting the Seeker who had a demon planted inside him, asking Cassandra to kill him to stop the pain? I'm even going to specifically call out that you say we don't see the Warden sacrifices when we blatantly do in two different instances: at the Western Approach and Adamantine Fortress.
You say that it's a weakness that the Mage/Templar war is resolved early and the Breach closed. That stretch is one of my favorite parts of the game. Properly evaluating the mage and templar situation is something it would have taken the Inquisitor the entire game to get up to speed on, and even then it would have felt a bit strange. The entire game's purpose is explicitly stated as being closing the Breach and stopping those responsible. Why exactly isn't this the primary reason for choosing a side in the war? And indeed, Inquisition recognizes this. When discussing who should be approached, your advisors broach more topics than simply "who is right" (as if that's likely to be a useful discussion for the Inquisition at that point and time). Instead, more practical topics are discussed. Who does the Inquisition have the influence to approach? Are the mages dealing with Tevinter and should we intervene there? What's going on with the Lord Commander Templar? Perhaps most importantly, who would be able to assist more efficiently in closing the Breach, you know, that end of the world thing going on in the sky up there? Inquisition's greatest strength in who you pick is that it remains silent, allowing you to decide your own reasons for your actions. This is smart because motives will be complicated in what is a naturally complicated situation. Just see what a mess Mass Effect 2's Collector Base decision is when it comes to actually implementing motives for action in dialogue. Beyond that, it was a good decision to close the Breach early and then get destroyed at Haven, because it actually feels like the plot is moving. This is opposed to Origins, where the main plot sits and waits for the Landsmeet to happen. It's true that Inquisition doesn't really live up to that after Haven (Cory just sits and takes your victories with the Wardens and Orlais), but this is something that Trespasser fixes.
Speaking of Trespasser, we aren't just comparing Loghain and the Archdemon to Corypheus. We're comparing them to Corypheus and Solas. I could write more here about how Solas is the best BioWare villain since Sun Li, but I'm willing to just call this a wash.
Now, as for reasons why I feel Inquisition is clearly superior:
The game is actually about something. No, I'm not talking about "the plot" or "what happens", I mean thematically, something that imbues the events of the game with meaning outside of themselves. Mainly, I'm talking here about the focus on the character of a Chosen One and a complicated, nuanced discussion of organized religion. Simply put, Inquisition has the most mature and intelligent discussion of the role and importance (or lack thereof, if you choose to RP that) of organized religion that we've seen in a game. It doesn't posit Church leaders as either villains or saints like damn near every game out there (even well-written games such as Final Fantasy Tactics fall victim to this). It doesn't comment on whether religion is good or bad except insofar as it comments that both of those things can be true. Cassandra is the best portrayal of a religious person that you could hope for, someone who doesn't feel like a strawmen, but a reasonable person willing to see both sides but choosing to believe in faith. And I say this, by the way, as someone who doesn't have an ounce of spirituality in them. I can simply recognize and appreciate good writing when I see it. Similarly, the Inquisitor-as-Chosen-One is well handled. It actually kind of amazes me when I see people say that Inquisition sports the traditional Chosen One archetype. I'd say that perhaps BioWare was for once too subtle in its writing, except it wasn't really subtle at all in Here Lies The Abyss when they revealed that you were merely an accident, exactly like the villain says. Characters often tell you that whatever you belief doesn't really matter. The Chosen One as a religious reality is a separate question from the Chosen One as a political or social reality. As Varys says, power resides where men believe it resides, and the Inquisition is set to use that perception.
What this means is that quite a few characters in the game are actually manipulating either you or the Inquisition's followers. It's telling that after the Dawn Will Come you can go to Giselle and question her about some of these things. That scene, to me, isn't actually sappy at all, because it's Giselle making a calculated manuever to more or less brainwash the Inquisition's followers into believing you are Divine. Later, when it's revealed you aren't, you are given several RP opportunities to respond to this. Beyond your conversations with your companions and advisors, the best one is when Josephine asks what you should tell Orlais about the events of Here Lies. Do you want to lie? Tell the truth? Neither? Why? The game is riddled with these complicated questions about the central tenet of you-as-Inquisitor. What do you believe about your role? About religion? About the Chantry specifically? About the war? Does it even matter? You lament the loss of possibilities to be evil, but I celebrate finally having several viable roles to play within a given type of morality. An attempt at breadth is going to result in a loss of depth, and the Inquisitor, thanks to the focus of the dialogues in the main story, is given the opportunity to be more specific about specific topics than any previous BioWare protagonist, with the possible exception of the Bhaalspawn.