For this article, I'll put away that Slap Morrigan mod and get into a comprehensive list of fan-made patches that unobtrusively remedy various issues with the game, such as broken side quests, dialog continuity, imports, missing/unaccessible items, graphical glitches and nonfunctional game mechanics.
Whether you are a gaming "purist" or just a new player experiencing your first (few) playthrough(s), there are just times that you just want to experience a less buggy game without the usual frills packaged with most fan-made addons.
Before downloading anything, let's bone up on some patch history. If you own the Ultimate Edition, you will already be rocking the latest patch v1.04. Although a bunch of things have been fixed, still some things remain (or became) broken. You can find Dragon Age Origins patch notes from v1.02 up to v1.04 at Bioware Social. For legacy patch notes detailing v1.01 to v1.03, there's a forum thread for that.
You can get a comprehensive, but very spoilery list of glitches and bugs in Awakening here.
Dragon Age: Origins
- Dragon Age Rules Fixpack
Note that some changes may be considered tweaks or enhancements, not just fixes. This compilation includes a large number of fixes to broken gameplay mechanics in addition to some convenience or rebalancing game tweaks. Each change is packaged separately so that you can choose which one(s) you want to use.
- Unobtainable item BUGFIX
This mod fixes several items that should but can't be stolen/looted in-game, as documented in the Dragon Age Wiki. An update to this mod added fixes for Fang (wrong tier is given in the PC version) and Ageless.
- Golem Registry and Shaper's Life Reward Fix
This mod fixes the no reward bug of the quests "The Golem Registry" (if Shale is recruited, The Stone Prisoner DLC) and "The Shaper's Life".
- Tainted Blood Fix
The Tainted Blood (Power of Blood, Warden's Keep DLC) bug causes additional self-inflicting damage when you have Dual Weapon Expert passive ability.
- Mesh lightmap fixes
Default version of some of the level models can cause problems when calculating light maps for the area, resulting in some parts of it becoming unlit.
- Cammens Lament Quest-Fix
Fixes the Quest 'Cammen's Lament' from not being completable in some conditions.
- Zevran Dialog Fix
A comprehensive dialog fixing addon which goes far beyond the scope of just Zevran's interactions. (As a result, it is not compatible with many other dialog-related mods.) You don't need the City Elf Romance Alienage Fix if you are using ZDF.
- Leliana Fixes (non Dialogue Tweaks version)
Fixes some Leliana dialogues.
- DLC in Awakening and Awakening Fixes
This unofficial patch will allow you to import your Warden's Keep, Stone Prisoner and Blood Dragon Armor DLC items into Awakening. As a side effect, this addon reverts the Blood Dragon Armor chest stats back to it's v1.0 state (currently v1.1).
Instead, if you prefer to keep your v1.1 Blood Dragon Armor chest you could use a different fan made solution to get WK DLC into Awakenings by editing your existing DLC files instead of overwriting them: DLC Transfer To Awakening Patch
- Sigrun's Roguish Past & Law and Order fix
Fixes a npc disappearing after accepting the Law and Order quest.
- Silverite Mines Equipment Glitch Fix
This mod fixes the infamous Silverite Mines equipment glitch that causes you to permanently lose some/all of the equipment on your player character. With this fix installed the scene involving the Architect & Utha will display correctly (not against a black backdrop) and your equipment will be correctly removed at the appropriate time. The fourth experimental subject will spawn correctly and they will be wearing your equipment when you encounter them. You should no longer have to strip naked to avoid the bug.
- Blackblade Armor Dragon Drop Fix
This mod makes the High Dragon in the Dragonbone Wastes drop the items as intended.
- Armor Rune Drop Fixes
This simply adds a few of the Armor Runes to a couple of Random Treasure lists that should have them, as well as fixes the two lists that already contain them.
- Awakening Runes Fixes
Some Masterpiece and Paragon runes are incorrectly flagged as armor runes.
- Awakening Bugfixes
Fixes "What is Built Endures" and fixes the Baroness' magic stat reward only. Includes a manual fix (requires activating the debugging console) for Sigrun's Roguish Past.
- Advanced Tactics
Note that some changes may be considered tweaks or enhancements, not just fixes. This add-in fixes various bugs in tactics system, party members behaviors and AI. New conditionals are also added, allowing you to create more complex tactical setups. Installation of this mod may require you to redo your tactics setup.
- Morrigan Restoration Patch Dialog Fixpack
Note that some changes may be considered tweaks or enhancements, not just fixes. This mod restores several missing and fully voiced scenes to the game relating to Morrigan in addition to fixing innumerable issues with various parts of her dialogue not triggering correctly. The mod also restores several new party banter dialogs involving Morrigan, Leliana & Alistair. Also restored is the ability to betray Morrigan to the templars during the Broken Circle quest.
- Qwinn's Unofficial DA:O Fixpack
Fixes a large number of general and quest related bugs for v1.03, however, there are numerous reports of it causing certain quests to fail to advance in certain conditions in patch v1.04. Use with caution.
- Ostagar Mage Chest Key
Not really a full-fledged fix, but this mod adds a debugging console command to generate a key to the mage chest if you had unwittingly used it in Ostagar before Return(ing) to Ostagar...because, apparently, some keys are one-time use only.
Installing mods seem to be out of the scope of this article, so I'll leave you to fend for yourself for now.