Through my last few experience and customers surveys I have collected very important plugins for wordpress site. This plugins helps you to improve efficiency of your wordpress blog.
SEO Smart Links – SEO Smart links keeps track of your inter-links within your blogs. This helps maintaining links which helps in Google ranking. This plugin find related keywords and attach the link to respective article you have posted previously.
All in One SEO Pack – This plugins keep track of your all seo parameter. You can automate and modify you title, meta. Optimize fine tune Page Navigational Links. Avoid duplication content in wordpress blogs.
WP Super Cache - This Plugin helps in speeding up your site by keeping a cache of your important pages on your server. So when ever a visitor comes to your site and request for a page you site does not have to go through heavy scrips and fetching your database instead just push the existing static page to visitor.
WP DBManager - DB Manager helps keeping the back up of your database from which you can regenerate your wordpress blogs on different server. This will help you in case where something goes wrong with your server. You have to regularly take a back up of your database from this plugin interface. So set your alarm up for every week monday evening 9:00 pm to schedule your back up.
Google-sitemap-generator – This will generate an google sitemap XML file and will submit it to google regularly. Sitemap helps google understand the structure of your site and fetch all your new updates and all your pages in google for your next schedule google crawl.
So this are the few but there are many more which helps you fulfill your most of functionality of your site. I will post few more very soon.
