Kindly use compressjpeg.com or tinypng.com to reduce sizes and compress all your images and reupload them.
Lastly kindly use WP Fastest Cache plugin and ask hosting to have Zend Op Cache and PHP Server cache applied to your site or if they have NGINX available get them to use that.
With all the above steps i am sure your site will be faster. Theme is just part of the entire WordPress website ecosystem and our themes are coded to be faster.
Rest are all generic points i mentioned here.