The player character appears to have been implemented entirely separately from the slaves and as a result has some inconsistencies that weren't resolved, such as not being able to change the hairstyle. Currently the way to access to the player's hairstyle is by editing the save file, which is JSON formatted text. For slaves this option is found in the Customization tab.
The portrait organization and selection is largely run by the community. The unmodded game only considers the race names when selecting images, which are not provided. Mav never really got involved in the random slave images until recently in Conquest.
