Hey there, I can't really tell if it would be better, since RenPy doesn't allow for gamma manipulation. I have only a couple of image altering matrices to work with (https://www.renpy.org/doc/html/matrixcolor.html) mainly brightness and contrast. Feel free to correct me here :)
Hmmm, don’t know why they wouldn’t include that as a standard transform. Not sure if this is just hidden away somewhere but apparently a renpy-dev made a shader function for gamma correction. Hope that helps.