Having a hawkeye on the terrain in this NES doesn't seem too important to the game. For example, the terrain specific resources will be swallowed into the national territory as the borders expand. For example once a deer icon is completely surrounded by a nations borders, it is counted (in a separate graphic) as a permanent food resource, lest a special event happens which erases the resource.
I am already working with like 3 full sized maps, 1 blank with only resources, the other blank tracking only national boundaries, and the main one which combines the terrain, resources, and territories all into one. I may however, if you would like, have a map of just the terrain posted for reference to if there is any confusion.
The Terrain specific player attributes, (eg: Desert Player Weak vs. Tundra Player) apply to any battle between those players so long as the desert is attacking within the tundra players boundaries. If for example, The Tundra player has expanded south into the lush, if a desert player were to squabble with the lush city, the weakness vs. the tundra player would still apply. (Unless that gets too unrealistic >.<)
The Terrain specific territory sizes, will require more careful modification (done on my part), in which if a player expands from a city on dry terrain, to one on lush, the city on the lush would have the smaller territory, while the one on dry maintained its size. I did this to prevent someone from grabbing desert right next to numerous lush or mountainous resources, and then using the territory bonus of desert to grab it all.