However, what made me truly enjoy this game was seeing the parallels of what connected it to DAO and DAII, not necessarily because the story was so strong on its own. Is this an approach BioWare should do more of? Do you believe DAI had too much fan service and little attention for original thought?
Absolutely not. Dragon Age: Inquisition has the strongest Dragon Age story, and it isn't just a matter of fan service.
The writers have pinpointed exactly what world movements are taking place in the Dragon Age world and highlighted them for DA: I. Questions of the Chantry and origin myths have been bubbling below the surface since you first heard about the Black City at Ostagar. Origins didn't have time to really flesh out this plot point, though, because it was too busy introducing important groups in the DA verse: Orzammar, Dalish elves, etc. There's no cohesive theme in Dragon Age Origins; in typical BioWare fashion it's a matter of establishing vignettes that upon completion tie into the larger plot in some tenuous fashion. In Origins' case, this was through the Grey Warden treaties, which essentially served as an excuse to ignore the Blight for most of the game. Origins shows you some of the how of the Blight, but is largely unconcerned with the why. Similarly, it presents you situations that introduce groups such as mages and templars, but doesn't offer any real progress into the evolution of the social issue. Origins does have the best final act of the DA games, though, with important variations and epilogues.
Dragon Age 2 could have been the best Dragon Age story were it not for time constraints and a few gaffs besides. The idea is sound and I was happy to hear that BW is considering a smaller-scale personal story again for DA4. Unfortunately the game doesn't do much to make Hawke's rise to power compelling (ostensibly the hook for the game) and we all know the flaws with the third act. Act 2 of DA2 is still the best stretch of storytelling in the series, though.
Now we come to Inquisition. The mage/templar situation as exploded, and this has forced the Chantry's hand. The writers smartly tied this in with larger questions about the role of the Chantry and Thedosian religion in general, giving the player an opportunity to be a part of real social change at the macro level; something neither Origins nor DA2 attempted. Once you've identified the focus of the game on the political structures of religion and how they compare/contrast with actual questions of belief, the rest of the game falls into place. Corypheus, as someone once betrayed by his gods, is the perfect villain for this story. His story is a crisis of faith that mirrors Thedas at large after the Breach. "Where is Your Maker now?" he asks, but underneath we hear the existential despair of someone who once asked where his own gods were and heard silence in return. As the Inquisitor, you are the opposite reaction to Corypheus. Clearly you can't let him succeed, something which the mage/templar missions establish fairly early. Given that, how should you defeat him? Since you were gifted the key to stopping him, power begins to circle around you, and gives you the opportunity for real input about Thedas society and what it means to you, with the Chantry in particular being the operative focus. It's no coincidence that the game asks you time and again for your opinion on matters of both faith and organized religion, and ultimately it's your decisions regarding the manner in which you fight back against Corypheus that determine the new Divine and so the new path that the dominant religion in Thedas takes.
Inquisition is actually pretty elegantly constructed as a deconstruction of all 3 origin myths. The ancient magisters/origin of the Blight is handled through Corypheus and Solas, casting doubt both on the Chantry's beliefs on these events and that of the Grey Wardens (does killing all the Archdemons stop the Blights? Solas doesn't think so). Meanwhile, you as the Inquisitor and your dealings with the Chantry represent an examination of Andrastian belief and the myth of the Maker. Finally, the events of What Pride on represent a total subversion of the Pantheon myth. In all three cases, the traditional beliefs and expectations are subverted, but not necessarily destroyed so much as reframed: the ancient magisters were real and indeed carry the Blight, but didn't cause it; Andraste didn't give you the Anchor, but providence may have guided you to save the Divine regardless; Arlathan was destroyed by the elves themselves, but the Elven Gods were actual elven rulers that are immortal in some sense. More importantly, the game offers you role-playing options to actually give your opinion on these matters.
Now, Inquisition's story isn't flawless. The Orlesian plot is woefully underdeveloped in the game, and the ending is abrupt without much build-up. However, there's simply a lot more to actually discuss and interpet about Inquisition's story than there was with Origins and DA2, and this fostering of meaningful discussion is in my mind indicative of superior substance.