I really believe one of this games strongest points is the author being the artist. A picture really is worth 1k words.
One of my players asked if "everyone in the world has an extra head and a limb that looks like it would be great with butter!
I explained that we know what people look like so the art is to show what we don't what it looks like.
It would be great to have some art of just "clothing".
I know, pick up any clothes catalog...
But the people in Overpass have some sort of "style"...from weather, what it is easy to make, etc. My campaigns usually involve a lot of role playing and I don't want players going out to grab a beer in Tac armor! Even if its just sketches, it would be nice to see what is "acceptable" and what is "ok, they are here to kill this town!"
One of the best parts of D7D 3.0+ was the chainmail shirt. I don't think a Paladin would go with no armor; but Plate armor to go to the market is just silly.
The other option is what sort of impression the characters give when entering a town. For example, entering a town while wearing heavy armor and carrying heavy weapons means the local militia are going to be called out for a potential invasion/assault.
Now if the characters have a minion go into town earlier, hire several of the laborers to serve as temporary dancers/fan wavers/incense holders/palanquin bearers, dress up those people in semi-matching outfits, and use them as the intro to the group. The main part of the group will be carried on a palanquin, looking over the masses of beggars lining the street, with various laborers carrying incense burners around them so the local smell doesn't affect them.
The local brothel has had ALL of its girls hired out to be dancing girls/arm candy for the PCs. Treat this as an all-night purchase, but the PCs are just standing there with the prostitute, nothing more.
Their heavy weapons are carried by intact/decorated/cleaned/shined household robots, and each robot is chanting a list of names of various creatures/people the weapons have been used to kill.
In short if the players arrive looking like they are about to invade someone's armored home, they will be stopped. If the players enter as though they are equal or higher in social rank/wealth than the town nobles, they will get a different reception.