A default site structure: definite answer

Yes, great question! This is pretty much the go-to guide for many situations: https://www.julian.com/guide/growth/landing-pages

Hi Xander, here's a long-ish answer with a completely different take, but hope it's helpful for you:

There's a simple heuristic I now use to determine what to start the page with:

A: If your audience has an established mindset for the product and its need, starting with a Hero describing the product is not a bad idea. Less is more, to the point, nothing wrong here.
B: But if your audience does not have an established mindset for the product and its need, a simpler headline and short text isn't too helpful. Instead, start the page with "struggle-first" copy, copy that relates the visitor's struggling situation to them so they can say "I feel seen" and then proceed to scroll.

Example: when Intercom started, it didn't have a hero with a "what you get" headline, it had a Before and After illustration contrasting the struggle and the solution because their solution wasn't mainstream:
https://sharpen.page/jtbd/copywriting/yeah-but-apple-intercom-have-features-benefits-pages/

As for what to have follow what comes at the top, the heuristic is this: follow with a section that answers the question the previous section creates. If they scroll, it's because they want more, they're not sold yet, so continue with a longer-version of your pitch. Re-state what you've written in different words, relate to more struggling situations using "maybe" statements, or by using different ways to tell your visitor there's a better way. Insert calls to action along the way down the page, because relying on a single call to action is asking a lot of that call-to-action.

Typical landing page layouts might look familiar, but they give off a smell of safety, and because of that, they don't get shared much. Better to go with an unconventional but struggle-first page layout which will have the added benefit of getting the word-of-mouth going.

Monitor your visitors (heat maps, recordings, etc) and split test your copy. Data tells the story, not anecdotal opinions.