Trilogy-Wide:
A Lot Of Textures - Graphical overhaul using both AI and manual adjustments/enhancements where needed. Not personally a fan of AI upscales, but it has 760000 downloads for a reason.
A Lot Of Videos - Ditto with ALOT, but with the pre-rendered cutscenes.
ME1:
Community Patch - Fixes hundreds of bugs.
Diversification Project - Adjusts numerous background NPCs to bring more species diversity into the setting, adds NPCs to barren areas, rebalances hub populations to be more lore accurate, etc. Also restores some missing NPCS, items, and over 500 lines of dialogue. Note that this will override some settings in the Community Patch and requires you to also install
Halcyon Hairpack and
Advanced Weapon Models.
Pinnacle Station - Completely restores the DLC to the Legendary Edition, which wasn't included due to Bioware losing the source code.
MELLO - Restores the dynamic lighting that was lost from the original ME1, along with a handful of bug fixes, cinematic fixes, and optional postprocessing updates (bloom, motion blur and film grain).
Saren Stages - IIRC, Saren was originally supposed to gradually transform throughout the game each time you meet him, and Bioware scrapped this in favor of his more conspicuous appearance, but not before the transformation idea made its way into the script. This mod restores the original idea and, especially early on, helps explain why Nihlus and the Council could see him and still trust him rather than ignoring the blatant implants.
Dossiers Restored - Restores character dossiers from the defunct ME1 website as well as cut codex entries, For example. it contained additional facts about the Mako, more details about how humanity discovered the mass relays and built Arcturus Station, and other worldbuilding stuff. The only entry that was purposely not restored is the one about
the Harvesters due to its questionable place in canon and the fact that it was absent from the ME3 multiplayer website, which kept the other stuff. Requires you to also install
Private Message Terminal.
Appearance Modification Menu - Customize Shepard and your squadmates with hundreds of outfits and lets you override appearances in combat, even for immersion-breaking stuff like naked doll Shepard in the vacuum of space if you toggle the option.
Squid's Squad Outfits - Adds more casual clothing to every squadmate, like Tali wearing male Shepard's big hoodie from ME3. Requires you to install the Appearance Modification Menu first.
ME2:
Unofficial LE2 Patch - Fixes hundreds of bugs, same as the first game.
Miranda Butt Shot Restored - For Miranda simps wishing to undo Bioware's censorship.
Lighting Restoration - Changes lights, heightfogs, and dynamic lights to bring back the tones from the Original Trilogy version of ME2 for some scenes in LE2.
Mission Results Screen Fix - Fixes the results screen being tiny and properly scales it to your monitor size.
Early Recruitment - Allows you to recruit any squadmate in any order as was originally intended, which had to be changed due to the game being split into two discs for consoles back then.
Cerberus Daily News Emails - Incorporates the defunct Cerberus Daily News articles that Bioware wrote for the main menu of the original trilogy, by adding them into the LE as emails. This only includes a third of them (or just over 50 articles), and only the ones more relevant to the narrative/games instead of every article. This is because there's 5 times as many articles as there are missions, so there would be no way to space them out realistically and you'd get absolutely bombarded with dozens of emails after every single mission. Only thing I'm not a fan of is the original "flavor" emails written by the modder for what's supposed to be a straight restoration.
ME3:
Community Patch - Ditto as the first two, fixes hundreds of bugs.
Diversification Project - Just like ME1, diversifies the game with better species and outfit/appearance balancing. Is subtler and more vanilla-friendly than Project Variety and is NOT compatible with it, so pick one.
Project Variety - Overhauls the game by adding new hubs, diversifying the Citadel population, restoring cut content, and much more, with thousands of changable options via mod settings. Has more bolder changes than Diversification Project and is NOT compatible with it, so pick one.
Expanded Universe - Mod Menu - Allows you to tailor which books, comics, games, and films you've read/played, letting other mods tailor specific content depending on what you toggle. This is required for stuff like the Diversification Project and
Take Earth Back.
Miranda Butt Shot Restoration - Same thing, but for ME3.
Anderson's Final Conversation Restored - This restores cut content with Anderson in the ending, extending the conversation.
Reworked Kai Leng or
Shut Up Leng - Changes Kai Leng to be less annoying. The former tries to keep as much of him as possible while the latter tries to removes him as much as possible, and both involve taping his mouth shut (or changing his dialogue for the former).
Admiral Daro'Xen Restored - Restores Daro'Xen's war asset that was apparently not ported over to the LE version of ME3
iOS Datapad Messages Integration - Implements the text messages you receive from the now defunct tie-in Datapad mobile app into the game. For those who don't like the vanilla versions of the messages or think they're flawed, use the
Datapad App Messages Expanded version instead, which expands on them like the name suggests.
Unextended Cut - Restores the original 2012 release ending for the morbidly curious.
Reduced Plot Armor - Adds a random chance of Shepard dying in cutscenes and includes a hard mode you can toggle for more checks, increased chances for death, and apparently a potential new ending.