Unlucky was a really interesting trade I think in Sims 3 and I'd like to see it return as I think it would really work well in Sims 4 I would also like to see the brave and cowardly traits return cuz ...
What about Speed Writer? I've noticed that when my Sim is in a flirty mood, I get her to write a romance novel but it takes so long to write the book that the mood wears off almost midway through writing.