Wow that's pretty in depth there and with a lot of hard to spot things as well, that does seem interesting if they decide to go for a story of Kratos going through the layers of the tree.
Norse mythology and the different levels of Yggdrasil are practically taylored to be made into a video game with different levels/chapters.
A screen of the demo that I found haunting:

Scary that even a giant can fall prey to whoever did this... D: