I first started editing the input.settings file to simply change the attack buttons to be more like Dark Souls but later added more changes that make the controls much more comfortable to use. After playing with this for over 40 hours I decided that I liked the setup so much that I share it here on the Nexus; no third party software needed.

Next to changing the fast and strong attacks during combat to use the RB (R1) button and RT (R2) trigger like it is in Dark Souls this mod lets you also accelerate your boat, swim/dive fast and gallop with your horse by using the RB (R1) button. This makes horse races, diving and sailing much more fun as you don't need to hold the A (X) button with your index finger (or your foot idk) while steering with the right thumb stick, getting a cramp in the process.

Overview:

General controls:
- Fast and strong attacks are now used with RB (R1) and RT (R2) respectively [Exploration, Combat, Horse (only RT)]
- Radial Menu is now accessed via X (SQUARE) [Exploration, Swimming, Combat, Horse, Sailing]
- Quick Access Items are used with LB (L1) [Exploration, Swimming, Combat, Horse, Sailing]
- Signs are cast with Y (TRIANGLE) [Exploration, Combat, Horse]

Swimming and Diving:
- You dive with B (CIRCLE)
- You surface with Y (TRIANGLE)
- You swim fast with RB (R1); this allows you to use the right thumbstick to steer Geralt and makes diving much less frustrating

Horse Riding:
- You attack with RT (R2); only one button to do that now as there's only one attack style used while riding anyway
- You can canter and gallop with RB (R1); this allows you to move the camera and steer Roach with the right thumbstick

Sailing:
- You stop with Y (TRIANGLE)
- You accelerate with RB (R1); this makes it easy to control the camera with the right thumbstick and look around while sailing fast

Installation:
Paste the "input.settings" file into C:\Users\USERNAME\Documents\The Witcher 3
Backup or rename your original input.settings file just in case.

If you've had added any custom keybinds for other mods make sure to re-add those in the new input file.

OPTIONAL:
The following file changes the "Swim Swiftly" prompt while swimming or diving from the default A (X) to the RB (R1) button so it fits the new assignment. You don't need this if you have disabled the button hints in the bottom right corner of the screen as you won't be able to see the old prompt in the first place.

Paste the "modComfortableControlsSwimFix" folder into the Steam\steamapps\common\The Witcher 3\mods folder. If you use other mods that change the hudModuleControlsFeedback.ws file make sure to merge any conflicts with Script Merger.

NOTES:
The only function that is now a bit harder to use is the alternate "Firestream" mode of Igni as signs are now cast with Y (TRIANGLE) instead of the right trigger. Locking onto enemies is therefore recommended to keep the stream pointed at your enemies.
If you find any bugs or have suggestions for improvements please let me know in the comments.