It doodad placement is neat, the map is pleasant to the eyes, but not something remarkable.
I really like your idea of having the right lane on shallow water and increasingly higher ground as you move to the left lane. Maybe you should terrain it in a way that emphasises it: Making the terrain obviously rockier on the left lane perhaps? Or adding high rock walls around the paths, mimicking a mountain? Just ideas.
And yes, it looks kinda flat as it is now, and close ups would be nice to see too!