Below is some additional rules for your htaccess file which provides some performance and security measures.
###########################
# Enable Keep-Alive
# https://varvy.com/pagespeed/keep-alive.html
###########################
<ifModule mod_headers.c>
Header set Connection keep-alive
</ifModule>
###########################
# Turn off etags
# http://davidwalsh.name/yslow-htaccess
###########################
Header unset ETag
FileETag None
###########################
# expires headers to your images and other resources.
###########################
<IfModule mod_expires.c>
ExpiresActive on
ExpiresDefault "access plus 1 month"
ExpiresByType image/x-icon "access plus 1 year"
ExpiresByType image/jpg "access plus 1 month"
ExpiresByType image/jpeg "access plus 1 month"
ExpiresByType image/gif "access plus 1 month"
ExpiresByType image/png "access plus 1 month"
ExpiresByType text/css "access plus 1 month"
ExpiresByType text/x-javascript "access plus 1 month"
</IfModule>
###########################
# Protects the htaccess files
###########################
<Files ~ "^.*\.([Hh][Tt][Aa])">
order allow,deny
deny from all
satisfy all
</Files>
###########################
# Disable directory browsing
###########################
Options All -Indexes
######################################
# protect the wp-config.php file
######################################
<files wp-config.php>
Order deny,allow
Deny from all
</files>
######################################
# SQL INJECTION PROTECTION
######################################
Options +FollowSymLinks
RewriteEngine On
# Block attempts to exploit by including '|' or '>' characters
RewriteCond %{QUERY_STRING} (\|%3E) [NC,OR]
# Block attempts to exploit using 'GLOBALS' variable
RewriteCond %{QUERY_STRING} GLOBALS(=|\[|\%[0-9A-Z]{0,2}) [OR]
# Block attempts to exploit using '_REQUEST' variable
RewriteCond %{QUERY_STRING} _REQUEST(=|\[|\%[0-9A-Z]{0,2}) [OR]
# Block attempts to exploit using 'php://input', 'data://', or 'expect://'
RewriteCond %{QUERY_STRING} (php://input|data://|expect://) [NC,OR]
# Block common SQL injection attempts
RewriteCond %{QUERY_STRING} (union.*select|select.*from|insert.*into|drop.*table|show.*tables|update.*set|delete.*from) [NC]
# Redirect to 403 Forbidden error page for matched queries
RewriteRule ^(.*)$ - [F,L]
######################################
# END SQL INJECTION PROTECTION
######################################
