The Forza Horizon games are the obvious choices here: all of them have huge, beautiful, varied maps you can roam around in essentially whatever car you want. One you seemed to have forgotten about is Need for Speed Heat, it's a similar concept but in not-Miami. I think the cities in it are way better than the cities in Forza, so if you are into street racing it's a good choice, but the areas outside the cities are significantly worse than Forza. I found the Crew and it's sequel disappointing, in my opinion the game simply has poor art direction, tons of pop in, and uninspired map design. However, when it comes to massive, varied, realistic worlds that you can lose yourself in for hours, nothing can beat Truck Simulator. Okay, you might not find trucks cool now (I was the same) or as exciting as supercars, but once you get into it you will. Euro Truck Simulator takes literally 3 hours to drive across the map....in both directions. There are almost 300 cities with all expansions. The scenery, signage, and road design are, in all but the oldest area, immaculate, and essentially identical to real life. It is the closest thing to a driving version of Microsoft Flight Simulator as a faithful representation of the real world that you can interface with exactly how you would with a real vehicle, and yet it scales enough that (like MSFS) it can be fun with just a controller or even a keyboard or mouse. It's an incredible game, even if you don't like trucks. Yet. Answer from dmklinger on reddit.com