Good deep research skills/plugins/etc? Built in defaults suck.

A Reddit user is seeking recommendations for deep research skills, plugins, or other tools, expressing dissatisfaction with the current default capabilities of ChatGPT. They note that built-in defaults "SUUUUCK now sooo bad" and are "useless now.. really weird." The user desires a tool that can perform thorough research on a given topic, taking more than five seconds to gather diverse sources and engage in a "really long long process" of investigation, similar to skills they previously used that have since changed.