Is it possible in 3dgs to make huge outdoor levels like in the game Black & White?

Can the engine handle:
- levels as large as in the game
- in combo with for example forests
- also with that many characters walking around

I have this question because I'm working on a strategy/sim which I like to set in a B&W kind of environment. As seen in the techdemo you can reach a grafically somewhat same admosphere. So all the graphical options of B&W are possible to get. It's a lot of work but still.
The only doubt I've got is the capacity of the A5 engine for huge levels with loads of entities.