First of all, a distinction can be made between the three settings "filigree", "normal" and "massive". This influences the design, which means that "filigree", "massive" or "normal" structures are formed during optimization. An example for the different settings is shown in the picture below. It should be noted that an optimization result with the "Filigree" setting is not automatically lighter than a "Massive" setting, because many fine struts can make the weight heavier than a few massive ones.
Figure 1: filigree, normal, massive