Best racing simulator: Automobilista (AMS), hands down. Superb FFB, amazing AI, very realistic in all aspects. Outdated graphics engine (but still quite good), no VR support. Dynamic night/day cycle, dynamic track, no rain. Lots of track mods available. Exciting car choices, including many generations of F1 cars. Runs on any PC. My all-time favorite racing game. (EDIT: If your are into online racing, be aware that there are few players available online at all times and most racing is done through leagues. However, the AI is so good that the offline experience is equally rewarding - and demanding.)
Best simcade: Forza 7, which could more appropriately be called a "car simulator". Over 700 cars, hundreds of tracks, acceptable FFB, gorgeous graphics. Plenty of customization options for cars. No VR, no dynamic time or weather; you can race in the rain or at night in some tracks, but that has to be chosen separately. Plenty of online & offline activities, lots of fun. (A bit more into arcade territory, I could also mention Forza Horizon 4)
Middle-of-the-way: Project Cars 2. Hundreds of cars, variable FFB – sometimes excellent, sometimes lacking. AI also tends to vary a bit between different cars/weather conditions. Wonderful graphics, great VR support, full day/night cycle, dynamic weather, dynamic track, even different seasons. No modding. For people who want realistic racing but don't want the learning curve that goes with AMS.
Of course this is purely a matter of preference. These are just my go-to games. I would also mention Assetto Corsa, which is a remarkable game, but does not have dynamic time/weather and does not offer many car/track options out of the box, although this is made up by the huge number of mods – with varying quality – available. After Forza 7, it is probably the game with most online players. And there is also rFactor 2, which has arguably the best racing engine overall, but is affected by somewhat uninteresting choices of cars/tracks and lack of a career mode. I like it at lot, but I almost never play it. This may change with the forthcoming release of the AMS pack for rFactor 2.
