Hello,
Can you, please, provide me FTP access to your site to your site to install cache plugins and check page speed with our theme and with the default WP theme to compare?
We’ll install Marseille 2 for you. Marseille 2 home page does not use the Revolution slider, we used our element to create the slider. If you prefer Revolution you can install and activate it from Appearance > Install plugins and then create sliders using plugin options.
If the problem is related to our theme we’ll give you refund.
Regards