Dedicated SEO pages vs indexing SERP's, is one better?

I posted earlier on this (thanks to those who replied!), but realized I wasn't asking the right questions.

My real question is- when it comes to dedicated SEO pages vs indexing SERP's, is one better?

Let's say we have a business index site that has businesses across 100 industries in 500 cities nationwide (so 500,000 pages, assuming content for each page). I want my organic presence to be as strong as possible, so I have a few options with SEO.

Option 1: I can have all SERP's indexed, e.g. .com/search/industry/computer-repair/miami (so all SERP's would need to be DB'd and stored)

Option 2: I can make dedicated SEO pages for each in addition to each SERP (so SERP's are dynamically generated and not indexed, and I have dedicated SEO-friendly pages too).

From both a technical and usability standpoint, I have a strong preference for #2. Most importantly, I can ensure content on the SEO page is very friendly and rich with relevant info that wouldn't belong on a SERP; probably more info than a person would be seeking if they went conducted a search from the home page.

What do you think? What's your preference?