It’s me again, the nitpicky backpack guy! Thanks so much for all your advice and tips! Here’s a comparison pic showing what I’ve changed based on your suggestions.
(Added highlights to the top flap; darkened the edge highlights at the bottom; added more shading to the backpack overall)
I think the edge highlights are too strong, and the shadows are too dark for how narrow they are. Do you have any other tips for improvements in case I decide to rework the backpack after work today? Or should I keep it that way?