Emotions and Traits Overhaul.

In the Sims 4, a Sim can have Evil, Mean and Hot-Headed for traits and still be the nicest Sim in the game.

In RPG games classes have limitations. A rogue/thief can only wear leather armor, mages are restricted to cloth and warriors can wear all armor types.

Traits and Emotions need to have limitations also. A clumsy Sim shouldn't be able to max out the fitness skill. This would affect the progression in the Athlete Career and Athletic Aspirations. Not everyone makes it to the top of their career path.

Traits should influence each other. Most traits have a positive when fulfilled and a negative when unfulfilled. When a trait is unfulfilled and paired with hot-headed, the response should be anger. A Sim with clumsy and hot-headed traits should get angry when they fall. Not just laugh it off. A hot-headed/squeamish Sim should get angry instead of uncomfortable. A hot-headed/animal lover should get angry if they are near a Sim using a mean interaction on an animal. If the traits are paired with gloomy the reaction should be sadness.

Emotions don't feel like they matter. For the most part, you can still do most of the things you already do. If you can't, you can easily override the negative emotions. Negative emotions should cancel positive buffs so they have more consequence. Negative emotions should have more weight against positive emotion decor items.

All dialog options shouldn't be available all the time. If a Sim is angry-spaghetti angry there should be limited friendly and funny interactions available. When a Sim is angry, a friendly interaction would be "grumble and walk away." A funny interaction would be "sarcastic remark." They rest of the friendly/funny interactions should be unavailable.