Shaded and highlighted the pants and boots, and tried a color for the shirt.
First: his boots. I always intended to make them brown. It occurred to me that with the olive green pants, those could be combat boots, which (as far as I know for the US army) would still be black. I thought about it. I decided I really wanted them to be brown.
As for the shirt, I'm not convinced on the color. It's sticking with the 'army' sort of theme that's developing for him, and it goes fine. However, I'm starting to be a little concerned that there's not going to be enough contrast. The boots, pants, shirt, skin and hair are all different colors, sure. But they're all similar brightness, and the green pants, yellow-green shirt, and yellow hair kinda...blend. The boots are brown, but brown is neutral and doesn't really help. The belt and backpack I was going to make the same brown as the boots, so that still will kinda blend. The gun will be black, which will stand out more. I was going to make the cloth tied around his right arm red, which will pop, and maybe also the rope. It's modern rope, probably nylon, so there's no reason it has to be hemp or sisal colored. I might go with black for that, too. So, if the rope is black, the gun is black, and the backpack and belt are brown, I could make his shirt, say, beige, and add some contrast via different brightness there. Ah...I also see I missed painting the back of his collar, there above the backpack. I'll have to be sure to catch that.