Thanks for sharing your thoughts. I'm afraid there may have been some misunderstanding, though; all of the screenshots at http://wordpress.org/plugins/easyrotator-for-wordpress/screenshots/ highlight features that are fully available in the Standard/free version. If you can please identify any information that you found misleading, we'll happily correct that.
The external editor application allows for more efficient and powerful editing features; for example, images can be resized and optimized before being uploaded to the web. This saves uploading time and allows for quicker development. Obviously, not every plugin is perfect for every use case. EasyRotator for WordPress is well maintained and offers extensive functionality. Many other plugins are more limited and/or don't receive regular maintenance. While the up-front setup usually takes a minute or two (as mentioned clearly in the plugin description), we believe that the long-term benefits outweigh the initial investment.