Exactly what I wanted to say. All that talk of “perfection” makes me imagine them snapping and going full psycho because a train was cancelled and they need to book a different one.
To OP: just stop trying to plan that much. A general plan is good. Just be aware things will change and that’s ok. As long as you two are having a good time, the rest really doesn’t matter as much as you think it does.
If you want a little psychological trick to make the trip more memorable than it otherwise would be, whatever you think is going to be the most impressive, save it for last. Our memories have a very strong recency bias.