Not random enough? Let me tell you about the day my sim family had yesterday.
Our teen boy went to cook something for dinner and set the kitchen on fire and caught himself on fire too! Thank goodness his mom and older brother were there to put him out or he'd have been a pile of ashes in no time. Then, later that evening, mom sim was abducted by aliens! I was really hoping the dad would be abducted because I just found out guy sims can return preggers from alien abduction and I think that would be hilarious. Not for him, poor guy, unless it was from encountering one of those green alien dancing girls from Star Trek TOS, guys really like her, don't they?
Joking aside, I understand what you're saying, 4 does play differently from 3.