I don't think it's entirely useless or at least no more than most, but I agree that a complete trait/personality overhaul would really help make traits like bookworm feel and look more distinct. I want all the traits to have more impact on behaviour and emotions. I miss a lot of the trait features from TS3 like how neat/perfectionist sims were the only ones that automatically made their bed, neurotic sims were calmed after checking things and washing their hands etc.