Enhance Site Optimisation Joomla Plugin

We have a joomla site optimisation plugin already working on the site, but we would like it to work better. By doing the following:

1. Enable Javascript compression

https://developers.google.com/speed/pagespeed/insights I've analysed the home page. I would like to gzip javascript before they go to amazon s3.

The high priority is below:

Compressing resources with gzip or deflate can reduce the number of bytes sent over the network.

2. Some Images and Jaavscript are not being uploaded to Amazon s3
http://tools.pingdom.com

Analysis of the home page - shows that some images and js not being changed by Amazon s3 plugin.

3. Activate Browser caching

As recommended on google page analyzer - I've added some browser caching in the site htaccess file, but this doesn't seem to have had much effect. we need to activate this feature.