well if they're planning a fall release, teasing it now would be a good time... and you know those pyramids would be a cool conspiracy story ... plus, you might want to rethink the setting not being ideal, here's some art depicting what ancient egypt used to look like...
https://www.google.com/search?q=ancient+egypt+landscape&safe=off&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj5y9nlgcPTAhXh6YMKHQY1AfUQ_AUICigB&biw=1567&bih=610#safe=off&tbm=isch&q=ancient+egypt+city
i'd love to see an ancient greece or rome, if we're going B.C. that is... and dammit, what's wrong with feudal japan or a chinese ming dynasty era? there's still so much in history to explore, they could be making these games for decades...