Gameplay-wise: Inquisition > Origins > Kirkwall
I am a huge fan of the offline MMORPG genre: my favorite RPG from the sixth generation was Final Fantasy XII, my favorite game from the seventh was Xenoblade, so of course Inquisition was tailored to my taste.
Inquisition finally boasts larges areas to explore, after way too many Bioware games which suffered from zones which were either minuscule (have you tried replaying KOTOR or Jade Empire recently?) or way too linear (why hello Corridor Effect 2), without falling victim the Skyrim syndrome of creating too large areas only fill them with dozens of barely distinguishable necropolises, ruins, sawmills built from the same limited library of assets.
The battle system has its fault, but having originally played through the console versions of Origins and Dragon Age 2, I see it as a clear improvement, has it makes micromanaging the team much more easy that the previous console versions (Although I'd really love an AI system as robust as FFXII gambits), while Dragons are no more mere static damage sponges.
Origins suffers from too many post-stamp-sized zones (the supposedly enormous Brecilian forest feels like a somewhat large backyard) and its battle system becomes increasingly broken as the story progresses, but at least it avoids Dragon Age 2's heavy recycling of levels and cheap, artificially boosted difficulty brought by enemies popping-up as reinforcement from nowhere.
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Story-wise: Kirkwall > Inquisition > Origins
Origins is simply too much of a power fantasy for my taste (although I understand why it is so, given that the devs wanted a self-contained "epic" story that would sell well for their first episode), and too many of the vaunted "moral dilemmas" are rendered pointless by easily accessible golden endings or design choices which incite to game the system (make a deal with the Desire Demon, get Blood Magic, reload a previous save, et voilà: Blood Magic specialization remains accessible without the cost)
Inquisition suffers from having too much of its meat reduced to side content (the Exalted Plains and the conflict with Freemen of the Dales should have been included in the main story, to name only two examples), from a cameos overdose and a weak chronology: the writers simply were not assertive enough in displaying the passage of time: by this I mean that instead of having Gaider mentioning in an interview that the game is supposed to cover a three-years -long period of time, it should have been mentioned in game: for instance, by having characters mentioning that, say, three months elapsed between the Battle of Haven and the moment Hawke arrived in Skyhold and that the year is now 9:42, by having the Halamshiral ball be explicitelly organized for the 9.42 fall equinox, by having Cullen mentioning that the Inquisition soldiers will have to celebrate the new year 9:43 en route to adamant Fortress, etc...
Still, I liked Inquisition's story a lot more than Origins: instead of a Super-Badass and her crew of loyal underlings swopping in and saving the day, we get to see an organization dealing with the aftermaths of conflicts begun before its inception, slowly gaining prominence as it does its best to mitigate the effects of these pre-existing conflicts: I'd loved to have something similar to exploring the Exalted Plains' ruined villages in Origins: the closest we came to that was Honnleath, which was
- a sidequest hidden behind a paywall
- Way too utilitarian (the Warden is not stumbling upon one of the supposedly many villages destroyed by the Darkspawn, witnessing the urgency of their quest: the Warden came to Honnleath to get a Golem: the Darkspawn acting as a mere diversion)
- Too clean: sure, we see some red stuff on the ground and a handful of hanged corpses, but the buildings are still standing, the countryside is still as green as usual (well, what passes for green in muddy Ferelden), and you just don't get that sense of devastation you get in the Exalted Plains.
Dragon Age 2 often has problems when it comes to properly displaying its story (like the fact that Kirkwall barely changes between acts), problems linked to its rushed development, but it still manages to tell the most engrossing story: Hawke's stakes and ambitions are much more personal, his/her small triumphs and great failures weave a tragedy far removed from the predictable trappings of its high-fantasy predecessor, the more linear structure of the game allows for a tighter narrative and even if Kirkwall remains too unchanging, the passage of time is deeply felt throughout the game via the changes in the Hawke household. Most importantly, its bleak conclusion gave the Dragon Age series the tone it needed: if you're going to write the story of an age of turmoils, you must make sure that some of your heroes fail.