What would you like for me to add on? The egyptian religion/belief system was a constantly evolving thing that often changed when someone else sat on the throne, or when the cultural climate shifted. What seperates Egyptian myths from most other myths is the change I am talking about. Not too many religions have gods that are constantly changing roles over a period of time or being removed from the pantheon because of assimilation.
My personal belief (and this is based on a lot of reading I did back in the day all the way up to two years ago) is that the egyptian "gods" CAN be linked to real humans (royal bloodline) OR they are linked to the Nephillim.
Here is something to look into if you're interested:
http://www.mystae.com/restricted/str.../watchers.html