I just did a major SEO audit for our site. Changing title tags and h1 tags are insanely important. It literally looked like we were hiding ourselves from Google. I'll probably do a post soon about this on our/my blog.
Also how does the HTML5 heading system (where you can have multiple h1s on a page) affect SEO, do you know?
Search engines are dumb. Make everything really obvious to them.
In my experience, I've seen the opposite. Well done h2s in fact, can really boost a series of site's rankings.
No doubt your page also can get ranked using the normal h- hierarchy.
The point of this technique is to put as much value on the main keyword as possible. Make it really obvious to the search engines what your page is about. Your page may have other requirements, so use accordingly.