Original content with good points is very important. The content must be useful for the readers and keep them engaged. If it is a professional website or a static page website then add keywords in the content. Select a keyword in the content and set a hyperlink to your own website adding again keywords as the title for the hyperlink. A page with at least 3 big paragraphs is good. I have created many websites for business such as hospitals, restaurants, schools, etc. I would put the main points at the top of the page and all my content would go down. Too much of content for hospital website, restaurant website and school website is not required and takes away the professionalism of the website but I would arrange it in such a way that the page looks fine and the content is also there. The SEO results are too good.
From olden days till now “Content is the King”. If it is a blog then writing more and more will help and boost the rankings. If it is a website then keep adding small contents daily. Revamp your website at intervals. Add some gallery images. Keep writing about offers at regular intervals.
When you add content be sure that it is not copied from other websites. Make sure it is an unique and new and fresh content. Add keywords in the content keeping in mind the density of the keywords. Don’t just go for hot search keywords, add long tail keywords and LSI Keywords also are very important.