To be fair, the anime adaptation of the novel exists. It's the movie "Night on the Galactic Railroad" (1985) and it even has a decent English dub. I'm guessing it was also made as a loose adaptation because most characters were drawn as cats (cheers
@CrazyKittenLady ) but the anime version of the story is probably the best known outside of Japan.
I know, I watched it to familiarise myself with the material before watching Hyoen.

The anime is based on a manga, which in turn is based on the novel. Both have adopted most of the original characters (although for some reason the artistic decision was made to portray most of them as cats

) and follow the novel’s storyline relatively closely.
There are many other adaptations in the form of musicals and stage plays that adhere to the source material to varying degrees, and from what I gather the general story is well known and pretty popular in Japan. I agree that the anime is probably the best known version internationally due to the English dub.
For Hyoen, Amon Miyamoto (who came up with the original idea before being replaced by Kikunojo Onoe as director) and scriptwriter Riko Sakaguchi collaborated to create their own story with mostly different characters, while staying true to the spirit of the source material by Kenji Miyazawa.
I would say that, even if you tackle serious and deeply metaphysical issues in your show/movie, it is always better to make all levels work. Which is, it is better if the story is also visually exciting, has a good pace, is emotionally relatable etc. because then it will also entertain the part of the audience that doesn't care about metaphysics. I'd say that all levels worked for Hyoen. But it does hurt my heart that they didn't for OPOI.
You have a point. However, imo that doesn't necessarily equate to having a huge production. Not all shows have the budget available to go all out with the production and some producers/production companies make a conscious decision not to drive up the costs in order to keep the tickets affordable, as was the case with Mao's tours and Kassouya, for example. It is possible to create shows with engaging content and interesting visuals that are able to captivate audiences on a lower/medium budget, as the aforementioned productions have proven, going by ticket sales/attendance and audience reviews.
Because the "One Piece" characters are exaggerated/larger than life, I personally don’t relate to them on as deep a level as I do with characters that are more grounded in reality to begin with, so I watch/read something like "One Piece" with a different mindset than something like “Night on the Galactic Railroad”. Both have fantastical elements, but the main characters in “Night on the Galactic Railroad” are portrayed as relatable people facing relatable struggles. So depending on my mood I choose to watch an ice show based on "One Piece" primarily to have fun, and a show based on "Night on the Galactic Railroad” to connect with the story and characters on a deeper emotional level. And I'm not saying one is better than the other – for me it's just different.
I suppose how each of us perceives these shows and whether they are successful in our eyes in their execution has a lot to do with our individual expectations going in.
The source material (the 2007 movie "One Piece: Episode of Alabasta - The Desert Princess and the Pirates") is low - if not the lowest - ranked One Piece adaptation which simplified the original story way too much. The original One Piece is a manga that contains its share of serious and emotionally complex messages, not to forget the visual and action-wise excitement it can bring. It certainly deserves better adaptation (talking both about the ice show and the source movie) and every follower of the original manga knows it.
I'm not an expert on "One Piece" (I've only read the first volume and watched an episode here and there), so I'll take your word for it.
Quantity evolves into quality and diversity, love that

I think that the development of Japanese ice shows is on the right track now and it is very exciting to wait what will come next.
Agreed.
I can imagine Koshiro and Kazuki working as co-producers
Let's throw Kosho Oshima into the mix as well to maximise the creative chaotic fun!
I think that, given the pace of development of original concepts, it is only a matter of time until Japanese ice shows start travelling around the world on the same right as Cirque du Soleil ice shows do - not because the audience is interested to see any celebrity skater but because the show is great. I guess we need to wait some years until this level is reached, so... it could be right about the time when Koshiro and Kazuki retire
I would very much like to see that happen, but I think it's very difficult because there is so much competition in the entertainment industry, even though I think several current Japanese ice show concepts theoretically have the right ingredients to be successful internationally. Daisuke has even cautiously expressed that he would like to tour abroad with one of his shows* and there were such considerations for Hyoen in the past (as Kikunojo Onoe hinted at in this
Luxe documentary), but so far these are still vague dreams, I suppose.
* For those who are interested: He said this in a recent, excellent documentary/interview that highlights Daisuke's endeavours as an innovator of the Japanese ice show landscape (since it was produced for NHK World, there are English subtitles and commentary throughout!

):
https://www3.nhk.or.jp/nhkworld/en/shows/2043094/
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