Improve AI Reply Quality and Style (More Humane/Relaxed)

I want the "Generate reply" and "Generate content" features to sound more humane and relaxed, similar to modern ChatGPT models or Claude. Currently, it sounds too obviously like AI trying to be a Reddit user and overuses em dashes, which introduces friction and makes me go back to external tools. Improving the model and system prompts would make the functionality much more valuable.