Contextual Photography & Pose Selection
I think players would really appreciate more two-sim poses that tell a story. This would pair really well with the implementation of pose selection. To avoid clipping problems that would come with mismatched poses, body poses could be set but have face variations. For an example: Sim A has their arm around Sim B's shoulders. You can change Sim A's face to look excited, proud, drowsy, smug, etc. Sim B's face can look excited, proud, drowsy, smug, annoyed, sarcastic, etc.
When taking photos of another sim, it would be great to get some touristy poses. Flipping a peace sign, pointing or gesturing in some direction.
It's jarring that teens and adults can't take selfies with babies, infants, toddlers, children, or pets (while they can with a pumpkin lol).
If a sim is holding an object, I find it disappointing that they put it away to have a photo taken! Sims holding objects--a football, an icecream, a book, a drink, etc-- could enable contextually appropriate poses. I would have loved to get a photo of my sim holding his diploma when he graduated from university or holding his baby for the first time.
It's great fun to make a record of the lovely memories you have of your little computer people, and I think options like these would make photos feel more genuine and unique.