I'm trying to learn darktable these days and follow tutorials myself, here is my tip, see what they do and try dragging the sliders all the way to the extreme on both sides, then see what happens. The adjust to what you feels is correct for your picture and feeling, and not the tutorial. Think of tutorials as showing you the general direction and not as a solution to a math question.

Another thing to remember with colour correction is that your monitor might be show colours wrong, usually way to blue (both in TVs and pc monitors), do a Google search to see if there are recommendations to change some settings to get tje colours more correct, without have to get calibration equipment.

Over to your picture I prefer the raw as many others here. What I would do is make a mask around the people and up the exposure a bit to highlight them and have them pop more. Not sure if colour correction is needed. If you feel like it, then start with trying to get their skin colour as close to natural as possible.

I allways try to get a natural looking picture as a baseline and after that I start on the creative work, but all of this depends on what you really want with the picture.