Alright. I've taken Chashio's sketch and moved in that direction. Fairly happy with the result. Made the rivers both slightly wider and darker with each convergence to draw emphasis on the "main" course. I also gave the rivers a horizontal preference to heighten the isometric perspective. I feel like the rivers don't quite fit with the rest of the style of the map, but it could just be me from staring at it too long.

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