re: Games (that don't exist) you would kill to have?

A true open world, online free-roam based, simulation-style racing/car-culture game. What Forza Horizon should have been....

TDU/TDU2 style fully open world (not just "open road") with 16+ player online free-roam as the default game mode, Forza Motorsport level driving physics and car catalog with full modification and tuning options, extended day/night cycle, weather, etc.

And yes, I understand there is not nearly enough of a demand for a game like this to actually be made. It will always have to be dumbed-down on the driving physics/tuning side appeal to the broader audience, a la Horizon. But hey, a guy can dream.