Use XML Based Sitemap and/or Static Page Sitemap?

Sitemaps have little to no effect on SEO whether they are XML or HTML. Sitemaps can help get Googlebot to crawl all your pages but they don't usually help Google decide to index the content, or rank the content better. See The Sitemap Paradox.

HTML sitemaps were once popular for SEO, but have since been largely supplanted by XML sitemaps. When I've had HTML sitemaps on sites I found that users rarely click on them, and when a user does get to them, they rarely find what they are looking for and click to another page. Furthermore, HTML sitemaps pages are low quality. Search engines are not likely to index those pages, nor do they pass much link juice through. These days, HTML sitemaps are more likely to hurt SEO than help it. XML sitemaps don't have the usability problems of HTML sitemaps. So while the are unlikely to help SEO much, XML sitemaps won't hurt your SEO either.

It is difficult to divine exactly why a specific page is ranking the way it is for a specific query. It usually boils down to a combination of the top ranking factors:

• Reputation: The site and page have external links and other signals that Google uses to judge the site as reputable.
• Authority: Google recognizes the site and its authors as experts in their niche.
• Relevancy: The page uses the search words or synonyms the right amount (not too much, not too little)

There are hundreds of signals that go into Google's ranking algorithm, so figuring out which one are dominant in any specific case is pretty close to impossible. However, the use of sitemaps is unlikely to be a ranking signal that makes much of a difference.