Seems to me you’ve used SiteOrigin for most of the design?
Have you tried the new Weaver Xtreme 4.0 Alpha version? It has some interesting new support for page builders. One is a new page template that is a bit more “raw” in how it treats page content and will use minimal wrapping divs for page builder content.
What might be more interesting the ability to replace the entire header area with content from a page or post created with a page builder, but with the option to use Weaver’s menus with all their options – fixed, fixed on scroll, etc. Can create some pretty cool headers that way.
You can replace the footer area the same way.