Slow cookers are terrible. The long drawn out cooking process destroys the texture and taste of food and turns everything into a homogeneous slop. So much time and energy usage for such mediocre payoff. And fundamentally not different to just baking stuff in an oven for a long time.

The real tip is to get a pressure cooker instead. Almost every slow cooker recipe can be easily adapted to a pressure cooker, for a significant savings in time, energy, and improvement in taste and texture. Even if you get anxious about pressure cookers, most pressure cookers have a slow cook function as well.