Monster Girl World

A monster Musume story

So,this is an issue I've been having for a while now: I can't write a good Monster Musume story. The issues I have are mainly with writing a protagonist, and which girls I'd like to add to the story. A few ideas I tried included a rogue team rocket grunt that now works for DATS with his renamin partner,a farm boy that works around his house which doubles as an animal sanctuary (inspired by the Urban rescue ranch) and a member of the Black Lily corporation. None of these completely satisfy me. When it comes to the girls,I don't just want to add the main girls,but also girls from the games like Belle,Ruka,Kalolo,among others, and the new monster Musume fantastic life game has introduced more girls that I also like. But I don't want to make the harem too big. And finally,the conflict; which I can't think of a proper conflict to deal with. I have thoughts of a few antagonists based on other monster Musume stories (and one hentai comic) such as a group of human supremacists, and a radical figure that calls for humans and monsters to go all out (with the issue being that he plans to split up current homestay groups, and he may or may not plan on stealing our girls for himself) the issue is that both these ideas are too serious and too...well, ridiculous.

So,what do you guys think? What should I do with a monster Musume story, and which girls should be in the harem?