I completely understand why people ask for that, but here's my reasoning:
I could absolutely rush the main cast and finish Hinata's and Himawari's questlines in just a few updates.
But then what?
The rest of the world would feel empty.
The way I'm designing the game, characters don't exist in the void, they interact with each other's stories. For example, in Hinata's NTR route, some of her future services can involve Ino. That means Ino's own questline needs to exist first, because the game needs to know what happened to her and what path she's ended up on.
If I rushed Hinata first, I'd just have to go back later and rewrite or edit a bunch of scenes to fit the new content.
So I'd rather build the world together, even if that means each update advances several different questlines instead of only pushing the main cast forward. I think it'll make the game feel much more alive in the long run.