here is a list of the best (and my favorite) plugins for wordpress.
First of all, if you’re not building your site on WordPress, I don’t know what you’re doing. So stop whatever that is and go get wordpress right now. And no, don’t get a “taylor.wordpress.com”, I mean, buy an actual domain like a grown up and use WordPress as your CMS.
These aren’t all free, but none of them are more than $40, which is basically free when their licenses are unlimited!
WP Smush
All-in-One WP Migration
Contact Form 7
W3 Total Cache
Yoast SEO