When you are creating WordPress website you should have the following plugin in your hand to make the site ready and launch in public . This plugin are related to security, performance , enhancement . Here are these:
When you are creating a website you should have a Contact Form , so, Wordpress Contact Form 7 is a great solution for it . Client side and server side validation , works with WordPress Recaptcha and WordPress Really Simple Captcha Plugin for captcha validation . Also you can use Contact Form DB to store details in Database.
This is needed for SEO purpose as it’s support meta tags , meta description each page, posts, even category , archives, and on home page also. Also through this plugin you can manage robots.txt and .htaccess file for better . Multisite comp ability adds a special feature on it.
WordPress Google Site Map Plugin , most needed plugin for wordpress site. As we always develop our site for a good SEO , so, fo Google XML site map is needed for a site . This plugin has the ability to ping google on behalf of you , when a post / page has been added . Also you can control priority on settings page.
After that all above plugin , you need to be think about the security of your site . Here it is , LockerPress , is good security plugin which is needed to hide wordpress admin login url , email settings for failed login, to change admin user .
Stop Spammer plugin gives you security over spam registration, comments from spammer . This is awesome plugin to secure , and prevent unnecessary data , junk in database .
The last one is not needed for every site but if you are thinking to place a support system in your site you should have this , this will work in two way , first you site will give online chat system , that will work as added advantage and secondly in offline mode it will work as contact support basis. I used it , and its really good.