Hello @leonidas111,
I am using the same patches as you (How to add camera support to libraw/darktable? - #6 by piratenpanda) with Canon R5m2 and I am quite happy with the colors I get from darktable default, when I import (color calibration:scene referred default + white balance: as shot to reference), as a starting point for subsequent editing.
What is better colors is a bit subjective and part of the creative process. So far I am able to render the final tiff or jpg the way I want, when it comes to colors.
From my point of view the camera is fully supported with the patch and the rest is creative processing to get desired result.
I usually add modules on top of default after import to modify saturation and contrast (color balance rgb, local contrast etc). I sometimes also modify color calibration, but I usually leave EDIT: white balance module unchanged.