To add to what some of you have been saying here:
I think 4 girls is a good number, though I believe if you have 4 girls it becomes inevitable that around 2 of them will have less priority, they will still be a "strong supporting cast", but they are not main characters. Main character, at least imo, are currently Rose and Cyanna. Esp. also because they are way more involved in the political machinations of the nation due to their positions.
I partially agree with you. Actually, this is where I see a chance for
N_taii to make the game a bit more complex. We know that ultimately - as a NTR game in the fashion of NTRPG, probably one of the few sequels in spirit that the game has (that does however also add new/different things to the formula) - there will be little choice for us regarding the NTR content. At best we can get a "bittersweet" or "revenge" ending if we make good choices and whatnot. BUT. I see a unique opportunity here to implement key choices in the story that do not influence our MC being cucked but rather how the game ends and with whom the characters end up. One such an ending could be the "Duke Overlord/Archvillain" ending where he indeed consolidates power and kills all his rivals one by one (including Ulrod) and gets all the girls in his claws. Another could be your choices helping to prevent this plot from happening and saving the other "villains" of the story and the girls ending up with them. Like for example in each instance there are things you can do so the plot to kill person X (i.e. the shopkeep, Jazon or Ulrod) is not killed. That will net you a small amount of scenes as end-content for these "paths" between the respective girl and the villain (i.e. Jazon and Hylen) as a "mini-ending" for their arc.
This can have all kinds of interesting turns. Like, like somebody mentioned, Ulrod joining us as a result of being saved in order to help fight the Duke at the very end. Same goes maybe for some of the other characters. Which will maybe increase your chances and make the ending slightly different. The variation doesn't need to be super big, it can just be a line of dialogue or two about what happened to/in the Kingdom, showing a few scenes of the kingdom and it's citizens that are appropriate for the scenario.
I do not doubt for example that the duke is the endgame or close to it. If his outcome if deciding on the "final ending" of the game, the outcomes could be something like:
1. (Mostly) Happy Ending: Duke defeated, Rose Queen, you by her side. You got cucked but you prevailed
2. (Less) Happy Ending: Duke demoted, still holds power, Rose queen, you by her side. She has an affair with him in secret.
3. Bad-ish ending: Duke wins, has Rose, reigns the Kingdom, but you managed to escape and get a resistance going, you migth have been able to hook up with some other girl (optional)
4. Bad Archvillain ending: Duke gets all the girls (or Rose + whoever you did not save the villain of), reigns the kingdom, you had to flee and take refuge in some other country (you had the chance to hook up with another girl through some optional side-stuff)
In addition to the main endings there could be a few variations, depending on who you saved. Saved Ulrod? He helped you against the duke, and maybe he is still with Cyanna (depending on your choices regarding Cyanna). He could also die valiantly in the resistance against the duke and who Cyanna ends up with depends on your ending (1-4).
Same/similar things go for all the other girls.
Now let me note this looks like a LOT. What Im listing here are just possibilities. I'm not saying "less than this and I will be disappointed". Not at all. I do expect some of this to not be implemented in the end. I'm just saying these are all interesting and creative ways that you can TAKE the story and make a few neat variations depending on your choices, without taking away the main element of a NTR game which is that most of the game is basically cucking of the MC.
But yea, I see a lot of possibilities in this to create SOME variation in the storylines without changing the MAIN premise of the game itself.