1.1 About the harem issue: this came up when I read the comments and reviews. First, whether a harem works depends on the society. Early Stone World was primitive, while later on it became modern, and Yuzuriha and Taiju only got married after returning to Earth. So if this were a harem story, the protagonist couldn't possibly want Senku to revive humanity, because reviving humanity would inevitably restore modern social order. Back home, in a major modern nation, bigamy isn't allowed, and modern people would condemn mistresses and affairs. But if he didn't revive humanity, Senku would become his enemy. Knowing what happens later in the story, he couldn't become Senku's enemy, or he wouldn't stand a chance over in America either. Without Senku, it would probably take another few decades, or at least a decade or two, to free all of humanity from petrification. And before that, the protagonist would have to kill Senku to eliminate any future threat.
1.2 About traditional Chinese medicine and Western medicine: the main reason I made the protagonist a practitioner of traditional Chinese medicine was that the drugs needed for Western medicine couldn't yet be mass-produced in a primitive world. Whenever someone caught a cold or got injured, making cold medicine and anti-inflammatory drugs would take a lot of time. Traditional Chinese medicine only required medicinal ingredients, which could then be simmered into a decoction. Readers also gave me the idea of using pharmacology to make poisons, anesthetic powders, and so on during the Treasure Island arc.
1.3 About characterization: I've never quite gotten a handle on it. I always feel like I can't capture the personalities of major characters like Senku and Gen, and I've made a complete mess of their characterization.
1.4 Also, I've been changing the later plot as I