After playing through both games so many times over the years i have never felt the natural outcome of the series would be revenge. Just in the chapters covered Ryo begins to develop away from that. The first game has him adamantly hunting down Lan Di in a fit of rage and emotion, and by the end of the second game it felt like Ryo was already coming to understand that Lan Di may have very well have lost his father in a similar fashion to how Ryo lost his own, and that it was becoming a viscous cycle of malice and revenge. And that he was carrying on simply to get to the bottom of the relationship between his father and Zhao Suming, and to discover the secret of the mirrors.

I personally do not believe a fighting ending would be essential or appropriate to end the story on. Think about the behavior of Lan Di, he showed absolutely no interest in Ryo in the games, he seemed like he simply did not feel a need for confrontation or has a use for Ryo and is allowing him to blindly follow him. At the beginning of the game he kills your father in front of you and uses you as a bargaining piece to get at your father, but leaves you alive when he could have easily killed you. Lan Di could have also easily prevented you from ruining his plans on top of the Yellow Head Building. He had more than enough skill and strength to lay out everyone there and then some especially had he stepped in when Don Niu was still awake. But instead he just leaves glaring at you from the helicopter. The only time Lan Di comes after Ryo is if you take way to long to complete the games, but i feel that was more than likely in the games simply because only so much time was planned and laid out in game, going beyond that point would of messed up the dates in the plot line, or caused issues within the actual game itself in the AI or something.

But i feel like some kind of conflict, be it a fight or a verbal confrontation will occur, i just do not see Ryo attempting to kill Lan Di in the end. Or maybe they would simply give you two paths as to how to end the game, fall down the path of evil like Xiuying had warned her brother had by killing him, or simply prevent whatever crisis from happening at the end of the game, leaving Lan Di to live, and go to America to find Nozomi if she does not get drug into the fight somehow by the Chi You Men.

I wish i could actually see in some form what Yu had planned out all these years ago.