The best thing about Hunter x Hunter is the fact that everything is mysterious (mainly because the anime never ended)
This intention is very strong when it shows the dark continent and in the confusing system of Nen, in every action in hunter x hunter it receives more applause than in other animes because every action can mean anything because the anime's setting is unknown.
It's a kind of shounen and cosmic horror mixed, cosmic horror always works because the author can leave it open and the readers themselves interpret it in the way that terrifies them the most.
But I think that's just because Togashi doesn't really know what he wants to do with the anime
But the anime is good, Togashi really manages to put this mechanism of interpretation of cosmic horror well and in a non-lazy way in his work, like the fact that the anime is about children exploring the world, he is superior to most of the authors (authors in general not just anime)
... this mechanism of interpretation of cosmic horror in fact is used everywhere, especially in religions, symbols that supposedly only great magicians truly understand (like the tree of life in kabbalah) that I highly doubt anyone actually understands.
In modern philosophy they also use a lot of subjectivity, strangeness and beautiful words to create systems of philosophy that I doubt anyone understands but everyone pretends to understand because it seems cool (Land, CCRu, Deleuze)