A well crafted, well paced storyline with enough background so that it made you actually care about your characters and why they were made part of the main story. Freedom to build your character anyway you wished, fully customizable skill trees, specializations with an actual story behind their origin( why and how you became Arcane Warrior, Champion, Reaver, etc was actually explained), choices made had real world impact in the game, tactical combat that allowed you to plan your battles and prepare your party accordingly, SPELLS that actually worked like magic( not the flashy colored energy bolts that look like were shot from Star Wars laserguns)...
These are a few of the things that made DAO outstanding in my view. Could you say the same things about DAI?
1.) I would argue DA:I has a well-crafted storyline, though it does leave some of the pacing to you, so whether it's well-paced depends upon you. Granted, the story line is a little simplistic, but less so than DA:O if anything. (This is not a slam of DA:O - they had to introduce the world so the story line could not be complex.) DA2 has a more complex storyline and doing something different didn't pay off - now, we can easily say that was not purely the reason it didn't pay off, but I can see why BioWare went for the safer "Save the World" option with this one. I do care about the characters in DA:I, and I think the companions are the most complex, best crafted companions yet. We also get to see a lot of other interesting characters at all tiers of NPC. And I like the story of DA:O, but I think DA:I is better. Technically, I think DA2 is the only one that tries to do something really interesting with it's story - telling such a personal story over 10 years - but all the games have solid stories, as far as game stories go.
2.) The specializations are explained in DA:I. There are little bits of dialogue with people about them - at the least, the person you share the specialization with, and sometimes others (3 conversations for Knight Enchanter and its origin and tactics, with companions, for instance, plus a mention by Sera about it's "Scary"ness, but I won't count her as knowing where it comes from, etc). You also have to do something to get the specialization, which is an improvement. In DA:O, a few specializations were kind of explained, but many were not. But in DA:I, all of them have dialogue as far as I've heard (I haven't played all yet). You may have to have affinity with that companion, but that's no different from DA:O.
3.) The spells seem way more "magical" to me in DA:I, but that's a matter of opinion in terms of which "look" works better for you. It's also just that graphics have improved since DA:O.
4.) The trees in DA:I give me more freedom that the linear progression of skills in DA:O sometimes. The crafting element allows me more flexibility and customization on my skills. No, I can't assign attributes manually (I can via passives), and I am pushed to create builds that suit my class, but when you look at the factors involved, you have more flexibility and control here than in DA:O - it's just in different ways. It's okay not to like the changes, but to act like it's all just restrictions is incorrect.
A lot of these come down to what you're looking for. As the poster you responded to said, it depends on what you liked about DA:O and what you wanted to see improved. I liked the world of Thedas, the lore, and so forth, but I found the combat deeply, deeply lacking, and I found the classes not distinct enough (warriors and rogues shared way too much), except mages, and I found mages OP and not well balanced with other classes, and a lot of problems with combat and character development, which I felt were addressed in the later games. I also prefer open-world because it makes the world of Thedas come alive (it wasn't done perfectly, but it was done well for a first open-world iteration, and I have high hope they can improve upon it even more). I liked making hard choices, and I loved the choices getting more "gray." Different people want different things. What will matter in the end is sales and financial success in terms of where they go next.
The lack of documentation is a legitimate complaint.
This game needs documentation. It's a wonderfully complex game that is made often incomprehensible by the lack of documentation.
The need to hold anything down runs directly contrary to the previous games, and isn't mentioned anywhere (and should never be necessary anyway).
I hate this about games in general. Why isn't the electronic manual just in my Options menu for every game? Why can't that just be an industry standard? No, you don't have to print it, but let me read it within the game!
This game was not made for PC, it was ported to pc as a last minute decision it felt and they dusted off the old floppy disk with KB+M controls from some 1990 codemaster game that I forget the name of but was Epic at that time...... Try it with a Xbox or PS4 and you will feel the difference.
Just because the graphics are better on the XB1 than a computer that is better (assuming your rig is actually better than an XB1 - you are a stranger on the internet to me, and lots of people assume their rigs are better than they are - just sayin' and you don't list enough information to legitimately see if there would be any performance issues with your PC, though from what you have listed, I'm assuming you took the same care in selecting other parts and built the PC yourself, etc) doesn't mean it was a last-minute port. It's way easier to optimize for consoles than for comparable PCs because of all the variables in different PCs. Someone else may have an objectively worse PC but slightly different choices in hardware and it may run better on that too. The "good" part of consoles is consistently knowing what you're designing for - it is much, much harder to design for PC. They showed footage on PCs that looked great, so it can run great, but there seems to be too much variability so they clearly are running into issues with different hardware.
There's no way the game was "ported as a last minute decision." They likely planned a multi-platform release from the beginning (and possibly added the this-gen consoles later, though maybe it was earlier on too). But reliably producing quality on PC simply isn't as easy as doing so on a console, especially the this-gen consoles which have some of the benefits of PC development without the drawbacks. I'm not saying this excuses the problems they seem to have - and I hope they'll fix it - but I think leaping to "It's a port" is extreme.