Honestly, I'm using AI to give me a challenge, a theme, and 3 unique keywords, and to grade it as if the AI was a lecturer on Creative Writing Course in top 3 university globally. I write it as answer to the challenge, a concrete poem, with the theme of human existence. About the last blank line, usually I rest my poem about 1 to 2 days, in this specific poem, I just feels the poem looks like too complete/perfect, so I give a blank line before the last sentences.