optimizing ExtJS + YII app

I have a small YII driven app that is using EXTJS 4.1 as GUI. It has some grids. The job here is to optimize the complete environment with apache-php-mysql and the app itselfes. There are a lot of small Issues that will decrease the speed of this site. It needs to find best options to run the app with more speed. Test Environment is online - if you are interested I can give you access do first tests. Here a list what Pagespeed has found for optimizing: Reduce blocking resources (2) Inline Small JavaScript Inline Small CSS Minimize payload (6) Enable compression Minify JavaScript Serve resources from a consistent URL Combine images into CSS sprites Optimize images Minify CSS Minimize delay in page load (1) Avoid CSS @import Other (2) Leverage browser caching Defer parsing of JavaScript