How do you optimise article.

1-Must have Main keyword in url 2-Must be in title h1. 3-Must be used atleast 3 times used naturally in article. 4-Must have related/synonym keywords 5-Internal & External Relevant links 6-Images must have alt defined 7-Easy to read. 8-Proper Heading Structure. H1, H2, H3, list & bullets. 9-Meta Description 10-Tags

What else could be done to optimise it considering OnPage SEO?