We enjoyed Budapest but it is not a s well developed as we would have expected. Many buildings and streets are in disrepair and many building projects are unfinished. We were surprised that in the midst of all this was a surprisingly upscale shopping district (e.g., Prada, Armani, etc.)
We walked everywhere. Be very careful crossing the street. Unlike the other cities on our trip where pedestrians get the right of way, the Hungarians take no prisoners on the roads. If there is an underground walkway - use it.
The tour through the ship was a little different since we arrived on a major holiday so we couldn't go to the Parliament, which is a major attraction. However, it was the nicest weather on the trip and we enjoyed seeing the Hungarians celebrating their holiday in the park and square while we got a good history lesson, especially about the fall of communism which was being commemorated on that day. We stayed an extra day to see more of the city.
The two main attractions for us were the Jewish Quarter, with the famous and beautiful synagogue and the Parliament. Both are "must-sees." The synagogue was restored and is the largest synagogue in Europe. Budapest still has a rather large and vibrant Jewish community and the museum attached to the synagogue, as well as the memorial garden, are worth the visit.
The Parliament was the most beautiful building we saw on our trip, including all of the palaces, churches, and synagogues. It is an architectural marvel. Our friend who went on the tour with us happens to be an architect and he was amazed by some of the innovations and touches in the building.
We didn't get to the famous baths, so it would be worth spending two extra days to see everything.