@Smithy, I'm not an expert. I just like baking bread.
I know that you need to make sure that the gluten is well developed.
I just do the stretch and fold method and I often do it over a 2 to 3 hour period with longer autolzye rests.
I like to look for bubble development under the skin.
Almost all of the loaves are started in the CSO on the bread setting so that it gets well steamed during the first 10 minutes.
Larger rounds are baked in a Dutch Oven in place of steaming.
If I want a darker crust, I just bake it longer. But that doesn't make the crust thicker just darker.
I also think that the flour used makes a big difference.