An addition I'd really, really like to see is some sort of consideration for immortal sims. After a certain point, there is just constant death. NPC sims dying off left and right. Like 7 or more a day. This used to basically mean your sim was in constant mourning, but mourning could easily be ignored. Now, besides constant mourning we're also stuck in a constant state of grief. The instant one grief trait goes away, another one pops up to take its place. There needs to be a point, say 50 - 100 deaths, and after that point your immortal sim gets a trait like "numb to death," that stops them from needing to mourn or grieve over every sims death... and maybe stop phone calls as the incessant phone ringing off the hook when you know it's just going to be another death pop up gets old fast. I was really hoping the "Grims' Right Hand" trait would mitigate the grief trait but it hasn't done a thing.
Another option would be just to make it so we could actually mark sims we care about and would grieve over. I mean, just because my sim easily made friends with some rando while drinking at a bar doesn't mean that I as the player actually cared about that sim or even noticed what their name was.