I think that website builder is primarily used to create static pages, pages that would require a lot of effort, when changing the content, such as updating the link structure, etc.
If you are able to use WP, I believe that would be a better choice for the long run, as you will be able to easily manage the content on the WP site, and there are so many free plugins that you can add to the site, that can boost SEO-related purposes.
For long-haul efforts, I think going for WP sites would be a better choice, churn and burn included.