Debes habilitar la compresión gzip. También echa un vistazo
aquí, comprobaras los defectos y carencias de tu web.
En pages con muchas imágenes conviene activar el cacheado de las mismas. No se si lo tiene activado o no. Tan solo seria añadir algo similar a esto en tu .htaccess.
Código Apache:
Ver original<IfModule mod_expires.c>
ExpiresActive On
ExpiresDefault "access plus 600 seconds"
ExpiresByType image/x-icon "access plus 604800 seconds"
ExpiresByType image/jpg "access plus 604800 seconds"
ExpiresByType image/jpeg "access plus 604800 seconds"
ExpiresByType image/png "access plus 604800 seconds"
ExpiresByType image/gif "access plus 604800 seconds"
ExpiresByType application/x-shockwave-flash "access plus 604800 seconds"
ExpiresByType text/css "access plus 604800 seconds"
ExpiresByType text/javascript "access plus 604800 seconds"
ExpiresByType application/x-javascript "access plus 604800 seconds"
ExpiresByType text/html "access plus 600 seconds"
ExpiresByType application/xhtml+xml "access plus 600 seconds"
</IfModule>
<IfModule mod_headers.c>
<FilesMatch "\\.(ico|jpeg|jpg|png|gif|swf|css|js)$">
Header set Cache-Control "max-age=604800, public"
</FilesMatch>
<FilesMatch "\\.(x?html?|php)$">
Header set Cache-Control "max-age=600, private, must-revalidate"
</FilesMatch>
</IfModule>