I do feel like The Human Condition II: Road to Eternity is my least favorite of the three, but that's the case with a good many trilogies and their second entries. When someone creates a trilogy as effectively one giant film (it definitely feels like they made The Human Condition as one film, or at least the first two parts, which both came out in 1959), it does seem possible that the least impressive stuff will fall in the center of a story. But if you're already hooked from the first part, and something powerful is being saved for the final part, it's not the end of the world if the second part is merely very good, rather than great or perfect.
The Human Condition II is the film of the three with the jerkiest pacing, jumping around from one situation to another in a way that does make sense on paper, but can feel jarring while watching. These beats are all necessary, and they serve to plunge Kaji deeper into morally grey waters while giving him physical and psychological obstacles to overcome, all of which get progressively more strenuous. This part does also deliver some intense war combat near the end, which the series otherwise avoids (usually to great effect), so me not loving Part II as much while also acknowledging its action-heavy climax does make me think of The Lord of the Rings: The Two Towers a little... it feels wrong to compare to film trilogies that are so different, but in any event, I think both are great.
Part II still delivers an essential chapter to a powerful story, and I can respect that more on a rewatch, knowing pretty well where Part III goes (that one was hard to forget). My only other real observation is that I'm more sure than ever that Tatsuya Nakadai is one of the greatest actors of all time. He's at his most human and sympathetic in the first movie, but he also seems a bit clean and passive, all in a way that doesn't necessarily allow Nakadai to go big (his subtle acting is great, though). But Kaji begins to slip at this point in the trilogy, and that just lays bare even further how great Tatsuya Nakadai is, the way he can have this character feel consistent yet ever-changing.
