Should I use a custom page / shortcode or widget?

Hello,
I would like to do something like wp-snippets.com. For this I created my own custom post type, a page for the overiew and a single page to display the details. Now I am wondering if this was not the best idea and I should use a widget to display the category on the left side and one widget to display the entries or use one widget for both. Or is a shortcode better and more flexible? What is the best practice for something like that?

Thanks a lot, Sascha