A different angle on the question "Why is Holly working for Minerva when she is a successfull writer?" is that her second book could fail and without employment and further education she has no income. Holly is doubtfull of her abilities, so not relying on her second book would be in-character.
Since Eva adores Holly and everyone (Victor, her publisher, her fans) expect that her second book will be a success, I wager that Holly stays successfull, if only as a reward for her shitty privat life.
Branching from that, another topic occured to me. GGGB was great in giving extremely diverse endings. Characters could end up very successfull, but also get devastating fates. Arthur could be a millionair or die in prison, Eva could have the love of her life or commit suicide or be imprisoned, Jessica could redeem herself and be in a happy relationship or end up as a drug addicted prostitute unable to get her life together.
Currently I doubt that ORS manages to make such diverse developments and endings for its characters. Holly seems to be set up for success regardless if Ian and Lena care for her or not. She can get them as partners or even Mark, Marcel, Clark or Stan if the player doesn't link her with Ian or Lena. There is no currently no indication that she could end up broken because she was cheated on and she could fail in her career. Maybe her next books are shit if she is abused or is too busy fucking around, but there is no indication that this could be the case, the sexual empowerment is suggested to be good for her.
Its similar with Ivy. Jessica had highs and lows, flaws. Ivy seems successfull in her career and there is no indication that she has issues with men and relationships. Its hinted once or twice, but unless we get some drastic reveals and twists, I don't see Ivy ending up poor, drug addicted and alone. Even if Lena and Ian shun her, she is still successfull at Blazer, the gym, Stalkfap, and likely with Billy.
I have the impression Eva likes her characters too much and doesn't give them hardships like in GGGB.