What is still missing for you?

"Wenzel;15578598" wrote:
A social update for the sims, which provides us with actual gameplay (other than "click to interact"):

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I'd love if my sims actually liked or disliked each other because of their personalities and habitus. Their attitude towards each other should limit the kind of interactions available in conversations (while still giving choice to the player  - so conversation success-chances should be modified and need to be more transparent) and also the way in which relationships develop.

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Social space and time: Introduce plausible chances for sims to appear on lots, according to age, sex and habitus.

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Long-term feelings: Certain things (e.g. stress, depression, love-sickness, fulfilled love) should cause long-term moodlets that stay for a week or so.

I absolutely agree that deeper social interaction is a must- not just for 4 but for the franchise in general. Currently social interactions are largely just spamming whatever actions you want until a bar goes up. Sure, in theory certain traits might make the sim you're interacting react more or less positively to certain types of interactions, but I'd argue there are further steps that can be taken to make interactions more organic. In addition to factoring in the sims respective relationships like you mentioned I think it would make a good deal of common sense to have them react to the 'flow' of their interactions as well. For example, randomly telling a joke might not have as big an impact as using that action as a followup to a complementary previous action (what makes such an action 'complementary' to a joke would in turn depend on various factors; a sim with a dark sense of humor will appreciate a joke following discussion of a serious topic while another sim might be severely put of by that same interaction).

I also think that more can be done to distinguish important relationships beyond, once again, a bar going higher. Family members and romantic partners in particular should have access to special interactions as a result of their special relationships. It would also be cool if sims had strong desires to see certain sims in particular and would suffer negative emotions and penalties to social fulfillment if they go too long without interacting with that one particular individual. Spouses and children shouldn't simply be people who occupy the same residence as your sim; your sim should desire to have meaningful interactions with them on a regular basis.

"Movotti;15337840" wrote:
Memories, it would be nice if sims were a little more attatched to their loved ones, and had a bit more of a reaction to the loss of them.
The ability for some sims to hold grudges. It'd be nice if some sims didn't want to get back with their partner after they cheat.

"lunaoddity;15400903" wrote:
- Sims to acknowledge extended family (step-parents, uncles/aunts spouses, in-laws, etc).
- Reactions to the death of loved ones even if not witnessed or outside active household.

"Cynna;15583497" wrote:
I would like TS4 to please have more romance animations and more animations between family members.  These animations should be based on traits, the types of relationship, and the strength of the ties.

For example, I would love to see loving grandparents greet their grandchildren with broad smiles and a pinch to the cheeks.  When the parents aren't around, they could slip the child a piece of candy (cash for teens!).    If the grandparent is the grumpy or morose type, they could give the child a perfunctory greeting.   Likewise, the child's response should also be individualized.  A cheerful child could give a bouncy, ebullient response.  A mischievous child could roll their eyes and push the hands away from their cheeks.  A materialistic teen could stash the cash and rub their hands together in greedy joy.

These are really nail-on-the-head ideas as well.

I'm seeing a common theme: sim relationships should equate much more into social interaction than they do.