Yeah, I agree that it wouldn't really work if they tried to make The Last Ronin movie a sequel to the 1990 movie.
Also, I wouldn't mind a movie that included some of the more graphic/mature scenes in the Mirage comics, but I don't think they need to overdo it with extreme body horror or other extremely gorey scenes that would alienate even some mature viewers.
I'd settle for just a relatively faithful adaptation — adding extra over-the-top horror elements doesn't seem necessary in my opinion.