To have the real game look : fantastic :
Yeah indeed BIG BIG PC.

But anyone will be able to run it on a low PC in 800*600 and all parameters at low ,even in that case , models characters are great.

But differences from paramters bewteen LOW and MEDIUM is very big , evene for water.So HIGH is even more BIG difference.

Wih the tool editor , hope to see good new maps made by community.
The tools are so powerfull and easy to use !
Even for animals (fish,crabs ...) you have an icon on the map representing tehm and their paths navigation.

For AI you can place hide places spots (for characters to hide),
when they fight they can go to the nearest.
In my mind Unity is the engine with editors even if far from Crysis one
is the ones that works similar : panels and special icons on the level
to visualise paths, lights, sounds ...