I like 1 and 3. Avoid 4 unless you are very clear about why you went off track, how you addressed your issues, and why you are certain they won’t recur.
Most advice to applicants focuses on the personal statement and description of work or activities required to complete the initial centralized application
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It is always helpful to know the prompts and character limits. But if you are trying to mindmap and set up a strategy, read the article.
On the suggestions.
1) identity not challenge
2) diary memoir, not a professional essay
3) depends on the prompt (dilemma helping other people, ethics on agency?). Make sure to minimize overlap.
4) maybe challenge...tighten up and be specific on a challenge or context. "Mysteries" don't work well in short essays or interview responses.