Years of experience making websites and seeing how each change effects the ultimate result of the website has narrowed me down to these.
Clear Product or Service You want to sell and how a method for someone to get it.
Great Images that shows off your business with its roots. More authentic the images are the better it is for people to trust your business. The images does not have to be professional.
Clear target audiences for your product or service. if you have multiple, the distinction should be easy to understand.
Your passion in the industry your business is serving in ( this is mostly to make sure your website site is alive, there for better SEO)