A game like Total War where you can actually explore the battle from the soldier's viewpoint in first person, and you can control the soldier. And you can have AI vs AI battles to just spectate over.
Or a Battlefield like fps with 1000 player battles with squads and platoons. Like Planetside 2 but in modern times and with destruction(not half assed like bf3)
Or an open world game where you just ride bicycles all over the place.