Actor Allusion: The voice actor playing Perseus is Harry Hamlin, who of course was Perseus in Clash of the Titans. The game character even sports the same costume and, when first met, has dialog that seems to indicate he's come straight from the movie. Sadly, since he's meeting Kratos, it appears poor Andromeda will be eaten by the Kraken after all... but Kratos kills that, too.
How Kratos "defeats" Aphrodite. Not to mention the fact that Aphrodite would be the...ahem..."opponent" for the sex minigame.
Many fans guessed that the grave digger from the original game was Zeus. The revelation in Ghost of Sparta is quite anticlimatic: you just have to select this character in arena mode, or see his name in the credits.
What Could Have Been: In the third game, they planned for Aphrodite to draw a dagger in the middle of the sex mini-game and try to stab Kratos, forcing you to win a Quick Time Event to survive, but changed their minds.
This interview, (content starts 10 minutes in) reveals an alternate story for God of War 3. Zeus would have been killed at the beginning of the game and the gods from Egyptian Mythology and Norse Mythology would fight the Olympians and Titans for control over the world. The game would end with all the gods dead, Kratos killing himself to reunite with his family and The Three Wise Men following the Star of David.