Hi there,
1. Try this:
.entry-meta {
font-size: 13px;
}
2. You currently have this custom CSS making your excerpts smaller:
.generate-columns-container article .inside-article .entry-summary {
font-size: .8em;
}
That CSS can be found in Customize > Additional CSS.
3. This is likely a question for the developers of the breadcrumbs feature you’re using. I’m not familiar with it, unfortunately.
4. Do you want all of the comments to appear above the footer entry meta?