I kinda wish more games would look into the Animal Crossing style of sandbox. Rather than just blowing up stuff and stealing cars, it'd be cool to see what else a developer could do with a small but highly interactive environment. Seeing as games are usually all about the locations, it'd be cool to have a game that focused entirely on this- like an island community that the players joins. They could chat with the locals, trade items, build a crude sailboat and explore the islands off the coast, and soak in the scenery at different times of day.
Animal crossing + wind waker = Animal waker?
also, stealth kills help the waiting problem a lot, as it leaves a bit more margin for error overall and rewards your patience pretty well. if you have to leave everybody alive it often makes it more of a timing puzzle and a lot less satisfying.
That's why we have distraction (noise, false alert, etc...), no need to kill.