On other had, I am not sure why you insist on being able to achieve everything the game has to offer in one playthrough.Not sure why you are so against the idea of changing the character during the game.
It's plain obvious that some of the trophies are rewards exactly for playing the game again from Day 1. And the presence of trophies rewarding opposite, alternative styles of play also are there to suggest that there is more than one way to play the game. Which is not equivalent to playing all the different styles in one playthrough. For me, it would greatly depreciate any planning, strategizing or even fetishizing in this game if you could be a character that is an obedient pet one month, then a rebel without a cause the other; the most popular classmate and a hopeless loser in one. And the reasons behind that would be not story-driven (fall from grace, sexual corruption, overcoming obstacles), but trophy hunting. This is like wanting to finish a league season on both top and bottom of the table. Or winning an Oscar and a Razzie the same year, for the same movie.
I guess you may be shying away from starting the game anew because of the sunk costs, meaning you worked so hard to build your PC the way they are at the moment, earned that much £££ and the idea of starting all over with only modest boosts that the feats can be exchanged for is short of demoralizing. Well, I guess this is the price we pay for playing an open-ended game that is still in development. Sooner or later we'll all hit the wall of playability and regardless of how many deliciously perverse and impossible sexual acts we throw our character into, or how many rape assaults we evade, the game will become a chore and you will dread the thought of having to wake up and go to School/Docks/Cafe/Brothel/Flower stand/Temple with no prospect on the horizon of ending it one way or another. That is why I would like to see a main story line (that the player does not need to follow with a walkthrough opened on another tab, but still gives the game its structure and sense of purpose) or at least a time limit. I haven't gotten to Xmas yet and feel slightly burnt out already. Nothing, except the achievement hunger and gamer's curiosity incentivizes me to do anything other than what I was doing yesterday and the day before yesterday and the day before that... Hanging around just to trigger Whitney and earn 'Giddy Up' medal is exactly what I am talking about. The event is just there for the player to 'discover' but what sense of achievement is there in that? And how does it move the game forward? Besides yet another shiny disk in your collection and a couple of VrelCoins, how is the PC better or worse off for it?
It's not that I am against the idea of change, because I'm far from it. It's that I find, not just in this game but a lot of games of this generation, that change and customization comes all too easy and it feels like a lot of games, maybe even majority of them are built around the idea of change/customization and not much else. If you look closely, perhaps you'll notice that the main theme in virtually every game bar a few on this site is transformation, be it gender change or magical shape shifting or mind-breaking/corruption. Basically: grind to improve stats, unlock places and items, earn money to get items, equip with items and sit back and enjoy as character changes from pure to debauched, male to female, blond to redhead, human to cat, flat-chested to milk cow, nerdy loser to ripped pickup artist, shy peeping Tom to literal mother-fucker... I don't know, maybe I'm exaggerating, but the role-play game model of stats, items and level ups seems to prevail. (Either this or a virtual novel, which is not a game really, but a comic book with mouse clicks instead of page flipping). Which is fine, as long as there is a challenge and purpose in it and a game does not turn into a dress up party.