[WordPress Plugin] Attachments allows you to simply append any number of items from your WordPress Media Library to Posts, Pages, and Custom Post Types
I like this, and will probably implement it myself. Two thoughts:
Offer a Pull Request and make it easy for Jonathan to review it and add it to the plugin.
Rather than modify the plugin code directly, extend the class to add your own method (function). This could be done in your own helper plugin that loads after the Attachments plugin, or in your theme's functions.php. This way if there is an Attachments update, your custom modification isn't overwritten.
It will be good if the plugin have a function to shuffle attachments before get them in while loop. Example:
At my own work, I edit and add this function to
Main Attachments Class