YES! I'd love the surprise of seeing what combination of traits they get. Maybe, when they age up, it would come up with a randomized trait, but then you could change it if you want to.
And also, why can't children inherit traits from their parents? If one of the parents is a slob, why can't one of the children be? It's just genetics. And you would still have the option to change it if you want to.
I would also prefer if the sim has a bad childhood or toddler years, you should NOT be able to pick the traits, just like in the Sims 3. I want more consequences and spontaneity in my game.