Replacers are a common type of game mod. Basically, what you're doing is changing one file the game uses for a different file with the same name. You see this often with, for example, graphic edits:
I didn't like the way the original male sprites were shaded, especially considering the inconsistency with stock NPCs. So with that in mind, I tweaked the sprites little by little until I was happy with them.
I hereby submit this to the community, and respectfully request Amethyst's consideration for use as the official sprites. While that happens, here you go.
(I had posted the sprites in my intro thread, but you wouldn't look for sprite edits there, would you?)
Male sprites ver 1.7.zip