Out door scaffolding that reaches higher levels of buildings
Sniper murder scenes maybe even give the city public events where a large group gather and someone is shot in a big crowd
A movie theatre would be cool also
Some card games like poker
Character customisation
Also the computer you have at your apartment maybe have more use like sending emails to npc or getting case offers through computer emails
You could even add friend level stat with each npc so you could invite them to your apartment or they invite you for events idk 🤷♂️
Also maybe the option to be a killer your self and have a detective follow your track