Dead Writers Society

Light and fast wp_head() cleaner. Just activate it and all unnecessary code will be deleted from site header section. It will improve loading speed of your website.
This plugin will remove:
<ul>
<li>WordPress version</li>
<li>shortlink</li>
<li>Really Simple Discovery link</li>
<li>RSS feed links</li>
<li>all extra RSS feed links</li>
<li>wlwmanifest.xml</li>
<li>meta rel=dns-prefetch href=//s.w.org</li>
<li>the next and previous post links</li>
<li>Emoji icons</li>
<li>WordPress REST API</li>
<li>oEmbed</li>
</ul>
Feeds (RSS, RSS2, Atom & RDF) and comments feeds will be disabled and redirected to home page for security reasons.

Nietzsche – WP Head Cleaner

This plugin cleans up the wp_head() and removes unnecessary code.

Andy Whalen

WP Hooks is a plugin for WordPress that allows you to add JavaScript, HTML, or other code to your 
header and footer without modifying your theme. WP Hooks uses the wp_head() and wp_footer() hooks 
built in to WordPress to add content to your header and/or footer. It’s great for those who have 
custom JavaScript, CSS, or other code (Google Analytics, meta tags, etc.) in their header or footer 
and don’t want to or can’t modify their theme.
Find <a href="http://amwhalen.com/blog/projects/wp-hooks/" rel="nofollow ugc">more instructions and discussion</a> on the WP Hooks home page.

WP Hooks

WP Hooks allows you to add JavaScript, CSS, meta tags, etc. to your header and footer without modifying your theme.

Nietzsche – WP Head Cleaner vs WP Hooks