Maybe he run out of ideas? Introducing new girls and make up some story about them is probably easier than coming up with stories about the existing casts. I don't mind as long as it's well executed like the farm arc.
The girls from hot spring arc are pretty forgettable tho.
>It's sad that it all begun with the milk farm chapters
>opportunity for Darling to use all his practical skills and grow as a character
>absolute top tier titty fuel
>ending primed for some character growth and resolution before heading back to the main cast
>ditches it all for last minute lesbians the likes of which put Korra to shame
I will never not be mad