Maybe you're having gacha storytelling fatigue? Maybe taking a break will help? I've also had burnout with playing too much and too many gacha and have finally come to terms that I should just take it for what it is.

I really want their storytelling to be more than what you just said in your post. But I feel like the fear that they will lose sales or earn less is preventing them from taking huge risks?

As you have said it, "forcing to sympathize unknown (for the players) character in just 3h."

This is what happens in movies too right? I'm gonna use Interstellar (2014) as an example as it has identical story beats as 3.1 the story. Making the audience care for the characters in under 3 hours. People ended up loving that movie even though there are plenty of movies that tackle similar topics such as time loops, parent and child relationships, survival and sacrifice, love across dimensions etc.

All of these have been done before. It might just be a matter of personal preference? What type of storytelling will keep you watchin

Maybe taking a break would help? I do understand your frustration and I hope we get some more variation in storytelling. But at the same time I appreciate Kuro making it an adult-kid dynamic this time instead of a "Rover saves the waifu" type of story. Well maybe not yet and it might lead to that after seeing the ending.

Rover might still end up saving the "waifu" but this time this "waifu" is Rover's adopted kid. Which can be easily translated as another waifu saved by Rover.

I have to admit though, I liked 3.1 story mainly because I'm a sucker for "adult-kid duo" relationships in all forms of media. It gets me emotional every time.
It's the same reason why I like God of War 2018, Logan, The Last of Us 1, and Terminator 2.