How can I remove or substitute the default RSS2 template?

I did not find a way to replace the default feed, ‘feed’, but I was able to add a new feed, ‘rss-feed’, and changed the links in the header to say the new feed was the default:

function my_rss_template() {
    add_feed( 'rss-feed', 'my_custom_rss_render' );
}

function my_custom_rss_render() {
    get_template_part( 'feed', 'rss-feed' );
}

add_action('init','my_rss_template');

function custom_rss($output, $show) {
    if (in_array($show, array('rss_url', 'rss2_url', 'rss', 'rss2', '')))
    $output = site_url() . '/rss-feed';
    return $output; 
}

add_filter('bloginfo_url', 'custom_rss', 10, 2);
add_filter('feed_link', 'custom_rss', 10, 2);

I copied the file feed-rss2.php from the wp-inlcudes folder to my theme folder, renamed it rss-feed.php and modified it for my needs. After this don’t forget to update your permalinks in the dashboard Settings.