As usual, my advise is to play around with it. There is no need to go with white as a highlight shader. Try a light yellow or a if the colour theme is “under the water” maybe a light blue will do the trick. A warm green should look good for a dense forest, jungle feel while a shading with red would be an alarm colour. Think neonlight illumating the objects.
I hope this tutorial on finding colour for highlight and shading was helpful! Enjoy!
Here‘s a file with the ‘rectangle version’.