Don't add inexplicable new characters, can't be bothered.It's clear that the original female characters could have been deepened, the characterization could have been increased, the linkage between the characters could have been increased, and then the plot could have been written in a deeper and deeper direction instead of continuing to be spread out in a way that makes it seem like the plot is getting paler and paler.My suggestion would be to focus on the most popular ones, the female characters, and the plot could revolve around a few of them, adding more details (such as body language), dialogue that fits the setting better, and fleshing out the characters more.