LOL @ Pyramids in Hellenistic Egypt derail.
As far as I can remember, Cleopatra's actual achievments include grabbing power in an extremely patriarchal society (in some ways even more so than the Roman/Geek ones), and outmanouvering her brother - the one she was supposed to be just a spousal attaché to - for several years.
Actually the hellenistic dynasties had quite a few powerful women, they seem less patriarchial than the Romans, especially in Ptolemaic Egypt where the rulers actively tried to incorporate elements of Egyptian culture, like the brother-sister-marriage tradition while remaining culturally Greek. There were several female rulers, mostly as regents in the Ptolemaic dynasty (most of them were named Berenike or Arsinoe or Cleopatra, like all the men were called Ptolemaios).
Cleopatra is generally judged too harshly, her dynasty had been on decline for a long time already. Same thing happened with the Seleucid dynasty in Syria/ the Middle East, it just is not blamed on a female ruler.
Generally it seems that historical female rulers are judged more harshly, because there are comparatively few of them. They are also, as exceptions, remembered much more. Everybody knows Cleopatra VII, but not many people know anything about Ptolemaios XIII.
In modern times female leaders are still an exception, I can't think of many important ones in the 20th century, Margaret Thatcher comes to mind, Golda Meir maybe, Indira Ghandi, Benazir Bhutto.
Even if they are popular and/or successful, their style of politics is usually judged under the perspective that they are female. Maybe Thatcher would have been hated less if she was just as polarizing but male. Angela Merkel is quite popular even with the other political camp, but her passive non-polarizing style of politics is also often described as a feminine style of politics, be it positively, "motherly", or negatively, as passively scheming.