Some of the things I dislike about the default MHW presentation are the washed-out colors and the blurry graphics you get by using Anti-Aliasing, and this preset aims to correct that.

Disabling the FakeHDR effect will result in better fps and less changes to contrast and vividness, but the remaining effects are still going to be an even more subtle improvement, which I believe is fully worth using, as it brightens up the game, slightly sharpens the image, smoothens the edges a bit, and reduces the washed out feeling of the default look. The FakeHDR is the final touch, which may be too big of a difference for some, or just cost too much fps.

ReShade FX used in preset:

AMD FidelityFX Contrast Adaptive Sharpening (CAS.fx)
CMAA_2 (CMAA_2.fx)
DPX (DPX.fx)
Clarity (Clarity.fx)
HDR (FakeHDR.fx)

(The .fx files are included in the download, but you will likely not need them)

Shader packs used when installing ReShade:

Shaders
AstrayFX
InsaneShaders

(I recommend installing everything suggested during the installation, as it will give you more options to play with if you want to experiment. Otherwise, you need to install the packs mentioned above, or manually place the included .fx files into your reshade-shaders folder that is automatically created from ReShade installation.)

INSTALLATION:

Download MHW - ReShade Injector Helper and place it into the main directory of the game. This is required for DX12 users.
Download the latest ReShade version.
Extract the latest ReShade files into the game's main directory (replace older files if asked).
Place the Subtle Enhancement.ini file into the game's main directory (exact location doesn't matter)
Launch the game (if using DX12 you need to launch it using the provided MHW - Reshade Injector Helper.exe file)
Toggle the Reshade console and load the Subtle Enhancement.ini profile file

ADDITIONAL INFO:

Disable Anti-aliasing from the game's settings.
If you want an even more subtle effect, but still have an improved image, you can disable HDR (FakeHDR) from the ReShade console. This will also reduce FPS loss.
If you want a smaller FPS loss, you can disable Clarity as well.