I enjoyed it. The only thing I would say is that there wasn’t a lot of tension or risk of loss in the series. It was more a low key telling of a period in someone’s fictional life. It kind of left me wondering if the last episode coincides with the last chapters of the book or if the season only covers part of the book like what was done with Silo.
The only things JSON has over xml is that it’s easier to write a parser for it and the format is less verbose and less complicated. There are extensions to JSON that can add features that xml has and the JSON spec doesn’t have. Overall the xml spec is bigger and has more features but that also makes it overkill for many of the cases that it would be used in.