Start a new game. Once you have made a choice between the public or private route for a character, that choice will last until the end of that game.
My advice: every time you see a choice between a public or private route, save your game to disk and name it according to the name of the character for which you have to take a decision (for example: sluttown-usa-hometown-corruption-20240000-000000-routes-alex.save). Play one of the routes until you reach the end of content for that character (and keep on saving your progress regularly, of course). Later, you can reload that saved game and pick the other route to enjoy the differences.
Alternatively, you can keep two sets of saved games: one set in which you pick the private routes for all characters, and another set in which you pick all public routes. You may also need another set in which you explore Romi + Elliot's joint story arc instead of their separate public or private routes.
Another solution is to hack the game and reset the progress of some characters using the browser console. I started experimenting a bit with that, but this is not as easy as it sounds. It is not sufficient to reset the story level of a given character (e.g., SugarCube.State.variables.alexStory) because although this will seem to work for a while, this will break as soon as you reach the next level in which that character's picture is supposed to change to the next step in sluttiness. So it is also necessary to reset the pic level for that character (e.g., SugarCube.State.variables.alexPicLevel), otherwise that character will become invisible and it will not be possible to interact with them anymore. But that's not all: some characters also have additional variables that control if they are gone for a few days or if you have already performed some specific action for them or not. All these variables also need to be reset to the right values. And finally, some characters unlock other characters (e.g., India unlocking Romi, Elliot, Emma, later Leah, and much later Veronica). It is also necessary to reset the progress of these other characters at the same time, otherwise their pic level and other variables may be set to the wrong values when you meet them again. I have been working on the list of variables that need to be reset for each character, but this is not trivial and it will take me a while to be sure that I did not forget anything.
