I usually take my bread straight out of the oven and place it on a wire rack to cool. The "music of the bread" (loud crackling sound) soon starts and within a few minutes the crust develops a number of large cracks, as in the photograph. This does not really matter, of course, but for aesthetic reasons I would like to avoid it - especially when using a ribbed banneton.
I am wondering whether using a shorter baking time then turning the oven off but leaving the bread in it to cool might help? I remember from visits to a glass works that an "annealing line" is used i.e. the glass passes very slowly through a diminishing temperature to avoid cracking.
I bake at 230°C for 40 minutes. Hydration of my dough is usually between 53% and 62%.