I visited in December, low season, so the city was gloomy and pretty empty. Most shops were closed too. I cannot confirm how packed it is in summer but be aware that the streets are narrow so it might feel pretty packed in summer. The old town is however not that big but offers some nice buildings and houses that you can visit. They are similar in terms of the design and architecture but I had not seen that in other nearby old towns. They also have a show (few minutes) at the house near what used to be the whore house. The city can be visited in 2-3h if you go into many buildings, if not, you can even do it in 1h. Access the city through one of gates where you can buy tickets, otherwise you cannot enter some of the houses.

Hongjiang ancient city (which is NOT in Hongjiang city, which has its own ancient town that goes by another name.... figure that out) is in itself a rare example of a well-preserved ancient Chinese city that has not been turned into a Disneyland. Of course, there is still a rather expensive entry ticket, which is unfortunate, but the town itself is fascinating, rather like a living museum, with workshops, guild houses, and even an old brothel and opium den. Even if you don't follow the tour, the experience is educational. At the same time, the ancient town is still lived in, so it's really a unique destination. That said, there seems at the moment no hotel willing to accept foreigners in Hongjiang (neither the ancient city nor the modern city), which means you have to make the long and expensive trek from Huaihua, itself a nondescript and polluted city that is definitely not worth visiting. If ever the accommodation situation (or the entry ticket situation) should change, then Hongjiang would make a great "off-the-beaten-path" stop on an intrepid itinerary. As it stands now, I simply don't think the old town itself merits enough to justify the cost (300 RMB round-trip taxi from Huaihua + 100 RMB ticket).