All of the things you mentioned are factors but it is hard to generalize from them to specific situations. It is easier to address specific examples. For example, are you using sugar in the dough and, if so, how much and what is the fermentation protocol (e.g., room temperature or cold fermentation) and fermentation time? Then, what kind of flour are you using? The hydration may be a factor (because of its effect on the rate of fermentation) but it is not quite as important as the residual sugar in the dough at the time of baking, the protein content of the flour, and the general baking protocol.