Hi Steve,
Probably you are right in most of points you made, however, I wouldn't dismiss the local SEO. In terms of budget, obviously what you pay for is what you get and I would for sure stay away of agencies/freelancers/so called SEO gurus when they promise you that you will rank on page 1 by x amount of time.
SEO is a long-term strategy and usually, any effort will be seen after 3 to 6 months. And I would say, probably the most cost-effective tactic is content marketing, writing your own articles guided by an article brief (are some quite good out here, if any good SEO agency/professional would provide that when you hire them for their SEO services). Also, are some many other which are selling so-called SEO packages, and I ve seen these on small marketing agencies, or business growth trainers. All these are doing is to bring a bad reputation to the table as the efforts put in these are really low and the output will be low (as expected).
Anyway, dont dismiss the local SEO if is done with some guidance and having a strategy in place.