Tags change for better SEO

I have been researching SEO tips and it seems that spiders look for:

HTML Code:

<h1><h2><h3><h4><h5><h6><h7>

So it seems that it would make more sense SEO wise if the tag cloud used those tags for the sizing rather than the CSS.

It seems like it would be a pretty simple template edit, but I couldn't figure out where to do the edit.

I disagree.

Those tags are meant to indicate "headings" within a document structure. Excessive use such as being applied to tags that have no accompanying content would not be a good idea IMO.