(NEW) PathfinderAutoBuff*:
https://www.nexusmods.com/pathfinderkingmaker/mods/231
A fantastic buffing mod that is easy to use and quite smart. Its one failure is that it cannot understand metamagic spells properly, so you cannot use Extended spells with it. That aside, it's a phenomenal mod and I highly recommend trying it out.
Arcane Unleashed*:
Go to the Steam store and find the DLC for Kingmaker on its store page
Not a mod, but a free DLC that you can install from the Steam store. I just put it here because people might not know about it and it adds some extremely powerful spells.
No History*:
https://www.nexusmods.com/pathfinderkingmaker/mods/190
A great new mod by Hambeard that helps reduce save file bloat.
Save Perfecto (Varnhold's Lot)*:
https://www.nexusmods.com/pathfinderkingmaker/mods/154
Not a mod, exactly. Place the savegame file in your Kingmaker save game folder (located within Users/<username>/AppData/LocalLow/Owlcat Games). It will not appear in your savegame list in-game, but when the time comes to select your Varnhold Lot savegame for import, you'll be able to choose it. This is perfect for people who have lost their DLC save, or just want the DLC items.
Craft Magic Items**:
https://www.nexusmods.com/pathfinderkingmaker/mods/54
This gem of a mod has been updated by another user and can now be used safely since it's being actively bugfixed. It allows you to craft new magic items and also upgrade old ones, so for example if you find a +3 weapon you like, you can upgrade it to +5. Ultimately this mod is too powerful and destroys the game's balance, if you use all of its features - the main issue is that Kingmaker throws far too much gold at you, so enchanting your own items with insanely powerful effects is just too easy. I still use this mod to enchant weapons up to +5, though, since the game is missing the Magic Weapon spell.
Loot Checklist*:
https://www.nexusmods.com/pathfinderkingmaker/mods/170
A mod that lets you view the loot that is in the Area you are currently in, including enemy/ally inventories. It is a simple list of what you are missing at that moment, it doesn't however tell you where the items are. This mod is a godsend, frankly.
Scale XP**:
https://www.nexusmods.com/pathfinderkingmaker/mods/24
Allows you to set an exponential XP scale that means you can reach level 20 by the end of the game. Check the discussion tab for some good advice. I have personally tested the following values on the 'Exponential' setting, and they result in your party reaching level 20 at the end of Act 6, if you do all available content: Base XP Multiplier: 1; Divider: 15; Exponent: 2.5.
Hambeard's Better Vendors*:
https://www.nexusmods.com/pathfinderkingmaker/mods/173
Includes a variety of features, not least of which is the Vendor Injector: this remarkable mod allows you to instantly (as in instantly, on the fly, without even restarting the game) add any item to a Capital Square vendor, so that you can purchase it. It's a very lightweight and should be safe to use, as well as safe to uninstall after use. It's technically a cheat, but it's a palatable one for items which are proving hard to obtain, or have been missed. It's a nice way to solve Artisan RNG, for example - if you know you've unlocked a certain tier but the game keeps diddling you on RNG, you can just sell the item you actually received and buy the one you wanted. There are also items which exist in the game's files but not in the campaign, such as Twin Serpents. Another thing would be the Changestaff spell which requires a non-magical quarterstaff as a resource, which, oddly enough, is quite a rare item, but not with this mod. Many thanks to Hambeard for creating this mod at my request.
Bag of Tricks***:
https://www.nexusmods.com/pathfinderkingmaker/mods/26
I previously recommended Cheat Menu, however Bag of Tricks is constantly being updated and is by far the better choice now. It allows you to modify an astounding number of things, such as experience, gold, and so on. This mod is basically part of the base game, for me.
Cleaner***:
https://www.nexusmods.com/pathfinderkingmaker/mods/39
This mod does a few different things, but the principal thing I like is that it adds a 'clean' button to the loot window when you leave a zone. It removes all loot and NPC corpses from the zone, which reduces the size of your saves. I think this will help prevent the issue where loading times for saves begin to get longer and longer. Be careful when using this mod, so as not to 'clean' important items you haven't picked up yet, you can screw up your game! Notably, the screen pops up when you leave your throne room if you have things stored in your stash, so be careful that you don't clean your stash by accident.
Difficulty Modifiers Scale With Level**:
https://www.nexusmods.com/pathfinderkingmaker/mods/193
Changes the way that difficulty works so that the modifiers applied to enemies depend on your level. This makes the game a lot more managable on unfair in the early game and makes the game more difficult at the end. This is a must-have for my builds as otherwise the lategame will become trivial, even with Insane monster stats.
Respecialization***:
https://www.nexusmods.com/pathfinderkingmaker/mods/7
I now use this mod with all my builds (well, except for the Baron). There are some known bugs when you use this mod with certain characters, such as Regongar (portrait sometimes breaks - I can't confirm this because I use a custom portrait for him) and Ekun (can break his companion quest - just revert him back to vanilla for the quest (the party thing) and you'll be fine). Back up your saves before respeccing, and check the mod's description page for more details. Overall this mod is a must-have since it allows you complete build flexibility while using companions.
NOTE: I have noticed a bug with the Respec mod that can be easily fixed. When you respec a character that has levels in Sword Saint, the Chosen Weapon feature can fail to be removed properly. This causes problems if you respec into SS again and choose a different chosen weapon. You can fix this by respeccing to level 1 (not SS) and then using Bag of Tricks to remove the Weapon Focus feat - this should resolve the issue and you can then continue levelling as normal.