Alright, games I would recommend:
Based on how you liked DA:O you will probably like the Baldur's Gate series that inspired it. BG2 is generally considered to be the best of the series though BG1 has its charms and they are arguably the best games Bioware have ever managed to create (admittedly a rather low bar to exceed). These games don't have great branching story lines but there are choices to be made (along similar lines to DA:O), think of BG2 as a larger DA:O and you will not be too far of the mark.
If you are interested in story above mechanics (or don't mind real time with slowmo) then try out the Game of Thrones RPG by Cyanide, it is not a great game but the plot almost makes it worth it.
Another deeply flawed game that you may enjoy is Obsidian's Alpha Protocol, a game that manages to get almost everything wrong but provides one of the best webs of choice and consequence (C&C) I have ever had the pleasure to play through.
Since you liked Human Revolution you should probably play Deus Ex as it is better in
most all ways.
If you don't mind blobbers (games in which you control a party that move and act as a single abstracted unit, a "blob") then check out both the Might and Magic and Wizardry series. World of Xeen (M&M 4 and 5) is a very good game(s) and the Dark Savant trilogy is definitely worth playing (Wiz 6/7/8). Whether or not you have fun will of course depend on whether you like this style of RPG however.
Since you liked Morrowind you could try its predecessor Daggerfall, a few nice choices and some really fun dungeons in this game.
Wasteland may be worth a try since you liked Fallout 1/2 and they are the spiritual successors to Wasteland, but its sensibilities are very much grounded in an earlier age and it will come across as a bit unforgiving for someone raised on Bioware and Bethesda titles.
The Gothic series (well maybe not Forsaken Gods) are examples of open world games done properly and given you liked Morrowind then you may like those as well.
You should try Betrayal at Krondor, one of the best written stories told through a video game with decent mechanics to back it up and a fairly open world. The codex's own Roxor did a review of it here:
http://rpgcodex.net/content.php?id=173
Ah, what else:
You could try Knights of the Old Republic 1 and 2, I did not particularly care for them (don't much like SW) but they are very much representative of their respective studios. Biowares's game is reasonably polished and narratively sound but generally uninteresting while Obsidian's game has an interesting narrative while feeling unfinished (if you do decide to play KotOR2 then make sure you get the community restoration mod).
Since you liked Troika's other two games give Temple of Elemental Evil a try, it has one of the best turn based combat systems made in recent times (though the content of the game is the least interesting of Troika's works)
You should probably at least attempt to play an Ultima game, I would recommend Ultima VII parts 1 and 2 and perhaps Ultima IV given its historical significance.
Darklands is a great choice to play though I am not sure how well it lines up with your tastes. The same can be said of Knights of the Chalice (he single best implementation of D&D style mechanics I have had the pleasure of playing), it is a good game but all about the combat.
If you decide to play the Neverwinter Nights series then you can safely skip the main campaigns, for the Bioware game the main selling point is a number of very good community made modules for the game. For the Obsidian game (NWN2) the selling point is the brilliantly done Mask of the Betrayer (great story, weak mechanics like most of the series), you might also get some fun out of Storm of Zehir as they are often sold as a bundle.
For historical purposes I would suggest giving the Gold Box games as well as the Bard's Tale series a go to see if you like them, there are some real gems (and a few horrible games) amongst their ranks.
And that should keep you busy for a few years at least I should think.
) ?
) and "Choose your own Adventure" games, get the Age of Decadence demo - if you like it, there's an extended demo available through early access. Definitely a lot of C&C in that one. Combat can be evaded if you play it right. Interesting experiment.
