The lack of innovation and new concepts in otome games.

I don't think this quite fits the bill since it doesn't have any priests but you did remind me of this game I played once called Particles of Reality. It does have an incest route and includes nsfw. Though if i recall right you have to get that route from the dev's pateron (it's free though). It's very much not a happy ending type of game and the dev does call it a dark otome. So I would say it falls under the risky category?

This is also something that the voice works are suffering from too in my opinion. I hope the script writers explore new area, but then again, I understand that they need their work to sell so sticking to proven things are safer.

I mostly agree. Sometimes it feels like many games reuse the same character archetypes, settings, or story structures. I'd love to see more original ideas, different settings, or less predictable plots. That said, I also understand that those familiar elements are popular because they work and many players enjoy them. Even so, I always appreciate it when a game tries something new.