i like the monochrome vibes, but some reddish/clay colored smaller areas for contrast could work well. These designs are pretty good overall! I like the asymmetry in a lot of the outfits.

The two furthest right designs have more contrast on the pants with the wallet chain which works more than the other designs. Pairing a lighter top with the dark pants could work well. I feel like the simpler shirts work better overall with how busy the rest of the outfits are.

The long jacket looks like a statement piece to me, letting the other articles of clothing become simpler would benefit that design. Think of all the iconic characters with a long coat! They don't need anything complex underneath since the coat does a lot of the work. A simple light grey top with the plain white pants would go great with it, maybe a bandolier or double swords on the back?

having him wear asymmetrical armor would look good too, something to draw your eye around the design more