You have a panels-based site and you need to create a new panel widget for the site. Now; you have 3 options: views, ctools plugin and Fieldable Panel Panes.
In this session; we are going to learn these options for creating panels for using in any Drupal site.
You already know what views is.
Fieldable Panel Panes is an entity type where you can make any entity-related magic and use it as a panel.
Ctools plugin is another approach located between the other two options.

When you learn the advantage of each existing option; you'll have the ability to decide which one is better for your use case.