I've been adding to the codebase the expansions I'll need in order to do road and town locations based on triangles. The first chunk of edits I needed to do for that was also just what I needed in order to add something new to the civilized-wild distinction. Have a look at the latest map image; as usual, I recommend opening it in a new tab to see it full size.
Wilderness triangles are now divided into categories 1 through 4; on the map, these are indicated as bright green, olive green, deep forest green, and red-brown. The higher the rating, the more wild and savage that part of the wilderness is. What determines the rating is how many other wild triangles border the given triangle.
Hey, I've just had an idea: I could keep using the 1-4 ratings to find the base wildness, and I could add on something additive where the rating of neighboring wilderness triangles gets added on to the given hex's rating. Thus, there'd be no theoretical limit on how high the wilderness rating could go, if the geography turned out to have big chunks of wilderness.
I don't actually plan to do that, at least not any time soon -- I'll stick with what I have for now. But hey, it's an idea, might as well put it out there. One use for such an "expanded" wilderness rating might be that this rating could then act as a direct counterpart to the "infrastructure" rating I plan to use to on hexes. Perhaps a hex could have a measure of both, the one determined by number and configuration of civilized hexes plus a bonus based on town populations, and the other being based on number and rating of wilderness triangles in the hex. Hmm!
While working on this I also decided to make all water hexes all-wild (type 1); this is OK because now, with degrees of wilderness, sea triangles next to shore will be rated at the lowest wilderness rating, meaning they are the closest type of wilderness to being civilized.
If I used the "additive wilderness rating" proposed above, then, given the way I'm doing sea hexes, the deep and distant parts of the ocean would be extremely dangerous.