We must be playing a different game. Look at the rain as it hits the Batsuit, or the reflections as it cascades around the gutters on the clock tower. The diffused lighting from the neon signs, the debris kicked up by the Batmobile. It's beautiful, even on the weaker Xbone.
There's lots to do in the city, but you have to unlock the waypoints. The 250+ Riddler bits are done via chasing down the green cars that crop up every now and then, and I've had random radio messages about the firefighters. The bodies I'm not so sure of, apparently I need to listen out for opera music but I'm sure there must be a better way than that. The AR games are good fun as well as being challenging (50+ combo is much harder to get than I remember!), and I love how I can upgrade so much more than before.
It does depend on how much you've done in that 30mins, you may well be a way from unlocking these bits. The Fear Takedowns are just immense though, they're exactly what the game needed.
"Chav kids are like sand people. They're easily startled but they'll be back, and in greater numbers."