It's a good start, but Dennis has pointed to some design choices that could use some work. I'll second what he said, and expand on some of his points.
Actually, there are a number of collisions between mountain and city type.
I'd make the city type smaller and not reversed out—you want symbol types to be more distinct. Given your saturated land-ownership colors, you're probably right to reverse park and forst labels out of them... they may not need the halo. Consider a bolder weight instead to make them distinct. If they still aren't reading right, adjust the kerning SLIGHTLY (despite what Dennis says

)—I find reversed out type needs a little more kerning, like 10% tracking, to read the same as positive type of the same size and weight.
Is this actually land OWNERSHIP, or administration? Usually, at least out here in Minnesota, National Forests have significant private inholdings. Maybe in California it's different.
Consider whether you want to show Interstate highways different from ofther freeways, and also if an additional level of major non-freeway roads would be useful.
I think the county lines should be more texturally different from other lines; like some of the land ownership shapes, they denote a jurisdiction rather than a route. The highway line should be somehow different enough to make this clear... not sure what would work best, but I'd start with a much lighter tint but heavier weight line. Also, the color of the ecosystem border whould be different from the highway line.
I'm not sure about treating the ecosystem border as a dashed line. It still denotes a hard line, and ecosystems are fuzzily bounded. I'd look at options that involve vignetting/ghosting, blurring, or otherwise suggesting rather than delineating the boundary. Using such a generalized shape with a hard-ish line ends up looking like incompatible scales of generalization, if that makes sense.