I need to update the URL format from site/parent1/article to site/category1/article.

I see the process as follows:

1. Replace parent pages with category pages
2. Assign the right category to each article (parent1 > category1, parent2 > category2,...)
3. Change permalinks settings so that URLs use category instead of parent
4. Setup redirects to serve 301 from parent1 to category1,...
5. (If necessary remove parent setting as not needed anymore)

Am I missing anything?