ajayver

This plugin gives you the ability to change the appearance of your RSS feed. You can easily add images from custom fields, read more link, category list, tag list and any custom code before or after the feed items. Also, the plugin allows you to delay feed publication for several minutes. It is helpful, when you made some mistake and you will have time to fix it before the post went to RSS and all other services like facebook or twitter.

RSS Manager

This plugin gives you the ability to change the appearance of your RSS feed.

steveo619

Want a read more button which is easily configurable and full of features? 
Look no further!
Read More Buddy gives you the ability to hide text with out affecting search engines ability to find it. Simple to add to your page either using the shortcode or even inserting the shortcode by highlighting the text you want to hide and pressing the RMB toolbar button. 
With plenty of customization features and light weight structure Read More Buddy is the perfect solution for your site.

RSS Manager vs Read More Buddy