redirects on new version of website
I need to build a new version of an existing WordPress website (with Divi builder). Unfortunately, the site design is several years old and does not meet many SEO/SERP standards.
One big issue is that the structure is flat – URLs are "www.domain/page.html," where a page hierarchy should match navigation, like "www.domain/category/page.html" For example, a page URL currently is "www.domain/wrench.html" where it should be "www.domain/tools/wrench.html."
How do I structure the new site to have the correct hierarchy, which would require MANY redirects based on the old site without taking a beating on SEO/SERP?
There is not such a thing as a correct hierarchy.
For example, if you have nested categories, are you going to use /category/subcategory/subsubcategory/.../page? Or just the first one? Or the last one?
Flat structure has its advantages too. For example, when a category of a product changes, your URL stays the same.
But at the end of a day, it's your choice. It always depends on a use case and if you have info website, /category/article could be fine.
I believe you are going to have some redirect either way.