my arms are too long

Well, it could be. You need to consider if the length adds value or if it's just dragging on without advancing the plot or character development. Maybe compare it to similar successful novels in your genre.

It depends on the genre and your intended audience. Some genres allow for longer stories, while others prefer brevity.

It depends. A long backstory can be okay if it's really interesting and relevant to the character's development and the story as a whole. But if it's just filler or doesn't add much, it might be too long.

The poem that he held the moon in his arms was Huang Chunbo's quatrain.

It's hard to say exactly. But if a novel makes you feel like you're slogging through it and you keep wishing it would end, chances are it's gone on for too long. Also, if it has a lot of unnecessary filler or overly complex subplots that don't contribute to the main story, that can make it too long.

It really depends. Some readers think a chapter longer than 50 pages is too much, while others don't mind if the story flows well.

It really depends on the genre and the story. For some, anything over 100,000 words might be too long. But in fantasy or historical fiction, longer lengths can be acceptable if the story is engaging.

For most people, when a short story exceeds 7,000 - 8,000 words, it could be considered too long. It should be concise and focused to maintain the essence of a short story format.

I think when a visual novel exceeds 30 hours and the story doesn't progress significantly or becomes overly convoluted, it's likely too long. However, it also depends on personal preferences and the genre of the novel.

It really depends on the audience and the purpose. If it's for a casual pitch, probably more than 15 minutes is too long.