Like I said on my reply, for more control you can use the frontier_before_top_bar action to output anything. Disable both Top Bar Title and Description then on a child-theme functions.php add the example below.
Example:
function ra_top_bar_text() {
$tag = is_front_page() ? 'h1' : 'h2' ;
echo '<' . $tag . ' id="site-description">Your Text</' . $tag . '>';
}
add_action( 'frontier_before_top_bar', 'ra_top_bar_text' );