Navratilova not winning either the German or Italian Open titles during her career is not a hole on her CV in the slightest.
Yes they were always big tournaments for the men. However for the women it was a completely different story. Rome was pretty much meaningless and a joke of a tournament until Sabatini came along and got the Italian fans interested in women's tennis, and who cared about Berlin before Graf emerged.
During Navratilova's prime, Amelia Island and Hilton head were much bigger clay court tournaments than Berlin and Rome, and offered significantly more prize money. And her record at those tournaments was very good.
In the past on this forum I've seen people using revisionist theory to say that Navratilova skipped the meaningless Berlin and Rome to avoid facing Evert on the European clay. LOL if Evert herself read that she would laugh at the stupidity of those comments.