DAI is, quite honestly, a Frankenstein. And I say that with no offense to any reanimated monsters that may be lurking among us.
Bioware's philosophy is at the same time admirable and kind of backhanded. They want everyone. This is theoretically a good thing. The problem is, they want everyone, and they do it with the grace of a sledgehammer to the skull. Just sit there for a moment and tell me who DAI's trying to appeal to. The marketing and design on this thing is so convoluted that if you embodied it in one person, they'd have more heads than the friggin' Hydra and all be talking at once. It's an RPG! It's an action game! It's tactical! It's open-world! It's story-driven! It's exploration-driven! It's multiplayer! It's single-player!
Origins wasn't perfect, and I'll be the first to admit that. The combat was janky and awkward, but Bioware's 3D has never really been good, and their animation is just a hair above Bethesda in terms of "please, get help". It was a little too MMO-inspired, holding back possible character builds by tying weapons to trees so they wouldn't have to think up new things to fill the warrior class with. Hotkey combat has never been exciting in anything, unless you're the type who really gets off on playing your keyboard like a piano, and if that's your thing my hat's off to you.
Yet, it worked. Despite the shortcomings in the character build system and the combat, you could do a shocking variety of things. A mage kitted out for buffing and debuffing enemies, or kitted out for melee combat. Dedicated players even wrote and tested an entire list of spells you could use without having to sheath your weapon just for that purpose. As long as you met the requirements, you could use damn near anything. Don't like robes? Wear armor. Want a rogue that fights on the front lines or a warrior archer? Go for it. Origins found an odd sort of quirky charm that the DA games have kind of lacked since.
I liked DA2 for what it was. It was simplified by a lot, but I was (grudgingly) willing to sacrifice variety for better skill trees and more responsive combat. DA2 left a lot of Origins on the cutting floor, though, enough that a lot of players just stared and went "this isn't the same game any more". Then DAI rolls around, and I'd be hard pressed to tell they were in the same series if it wasn't for the words coming out of the characters' mouths occasionally.
Yes, Inquisition has some good points. They continued with DA2's better skill trees, but it dumbed the game down even harder than DA2 ever could. In a word, if I had to describe it, DAI is just "less". My character is, more often than not, a one-skill monkey. Warrior Smash. Rogue Sneak. Mage Shoot. Fighting mage? Arguably still exists in the form of the Knight-Enchanter, but you can't wear honest-to-God armor unless it's Silverite. Enjoy grinding that at one chunk per node until you hit an arbitrary level point that Bioware decides you should "have" it. Warrior Archers and Brawler Rogues were taken out back and given the ol' Yeller along with Healers and Maker knows what else.
Characters can't use multiple weapon sets. Characters can't use more than eight skills. One of which is a focus skill that takes up a slot and can only be used every once in a blue moon. Healing is gone, replaced by an even more brainless system where the mage just zaps you with Barrier and the warrior uses Guard, if you can ever get the blasted AI to actually do what it's supposed to. Which honestly, good luck with that "tactics" system. They just replaced post-damage healing with Temporary HP and called it a fix. You're still relying on either the AI to do it, or you to do it once it runs out. It's not tactical in any way, just more of the same micromanagement people complained about with healers.
The HP sink nature of enemies is even worse than it was with DA2, which I could almost forgive there because it was rushed to hell. In DAI, not so much. Fighting a dragon isn't difficult, it just becomes this long slog in which you chase it around, keep popping Barrier and Guard every time they run out, and watch the mile-long HP bar slowly creep down.
Not to say that the rest of the game is an improvement. I thought DA2 made loot worse by scattering it all over the blasted map. DAI goes one step farther and it makes it random. Then it adds crafting, which totally didn't take exploration in Skyrim out behind the woodshed and started beating it with a broom, and somehow makes it worse. Nobody has their own recipes except for the Orlesians, and to make it worse, a significant chunk of the bastards are completely random. Meaning that one piece that you probably really need you may never get. God forbid I get into the quest "rewards" or the economy.
And yet, it's not a bad game. I can almost forgive a bad game, if they have some sort of charm. DA2's a wreck, but it's fun in a lot of respects. Hawke and Varric carry it a long way, the character interaction is (generally) good, and even the combat has it's moments. DAI, however, is worse than that in the aspect it's just boring. It's been stripped down and hacked apart so much that it isn't even recognizable as Dragon Age, and even DA2 was sort of iffy with that. It's bland. Where it tries to improve, it takes a few steps backward and falls flat onto it's own back. It's dull. It's bland. It doesn't want to be red, or blue, or yellow. It wants to be beige. And it is.
How appropriate.
I almost think Bioware's DA team only really hears one criticism of a game and focuses entirely on that. DA2 didn't really carry on from DAO's strengths, and DAI doesn't carry any of DA2's - with the exception of the skill trees, which I do admit have potential. As samey of a replacement for healing as Guard/Barrier are, they're not awful. What I think could help is giving both players and enemies a wide variety of options back. It's not a solution, but it's a start.