My sites become more slow after installing wpmu dev plugins

Hi WPMU dev Team ,

This is Abhinab from Kolkata. I have more than 30 websites using wordpress. I run a small business here in kolkata, so I choose wordpress to increase productivity and deliver websites at a faster and cheaper rate to my clients.
I came to know about wpmu dev years ago but at that time I couldnt afford its paid subscription but always dream of it. Now when I can actually afford its subscription I am very much disappointed Sir.
After installing wpmu dev plugins like hummingbird or defender, sites actually became slow. In some site it is causing clash. When I disable them it works fine like http://www.nirmalyaroy.com

Mainly I am concerned about my site speed. Sites like http://www.aspiring-life.com, http://www.sangen.com.bd, http://www.uttarparasangeetchakra.org etc. they have a really bad score. loading time is huge. and as per your recommendation I tried P3 plugin to test which plugins are causing my sites to become slow or increasing the server response time, to my surprise i found they are hummingbird and defender.
WP Smush actually doesnt helps a lot as I expected while reading wp smush advertisements in my mail.
Please help so that I can make my sites load faster. It is very important.