Having a good preset really speeds up everything significantly. I have a standard darktable style I apply to every RAW image that includes:
- Input color profile (I use Rec2020 because it produces much better results for A6000 than the standard or Adobe ones)
- Base curve/tone curve (profiled for my camera)
- Profiled denoise (heavy wavelet denoise on HSV color)
- Profiled denoise (very low strength denoise on lumiance channel)
- Automatic lens correction if it is detected in EXIF
- Equalizer (for clarity boost with parametric mask to limit it in the mid-tone)
- Color checker lut (to emulate fuji astia film)
- Highpass sharpening
These gets me about 80% there. After that, I usually tweak (which will vary for each photo):
- Exposure correction
- White balance
- Shadows and highlights
- Color zones to selectively lighten/darken/(de)saturate each color
- Tweaking denoise options for high ISO images
- Vignetting, GND
- Crop, rotate, keystone/perspective correction
Finally, it gets loaded into GIMP for healing, selective sharpening, dodging and burning, etc, if they are required.
Processing an image can take anywhere from 2 or 3 minutes to basically infinite. Most of the time problematic ones are those with mixed lighting, and sometimes my taste changes and I go back to re-process my older photos as well.
After processing a batch of photos, I also find it very useful to let the photos “settle” down for a while (if getting the photo out quickly isn’t the top priority). Go do something else for a few hours and come back to the image, you will usually discover flaws in your editing that you glanced over in the first time.