This is pretty cool. I put in a cross country query and it got it done, took about 30-45s. I was kind of expecting a granular plan including specific bus / train numbers and times. But I understand why it does not do that right now. Probably public transit is not very timely or reliable anyway and the plan would not actually come to fruition in any case.
However it feels like a very cool technical challenge to include specific timings - which also would unlock a headline total est time.