When I look at my Xbox Library it consists of a real large part Racing Games. Forza, NFS, F1, Grid, Colin McRae and so on. I enjoyed most, one better than the other because of better handling or feel. Yet in the core, the story side or skeleton of the game exists of Racing, earning money or cars, upgrade them a bit and Race again. Online most cars are mostly the same exept for a different coating.
Now, I played MH and thought to myself....What if there would be a racing game that puts the MH core gameconcept at its own core. Race, find fluids, special items, finish, get extra sponsor parts, but only a few of them. Every Race has its own style of enemies and surroundings. Go to your garage and start building your custom cars. Rally, Ice, Snow, Water, Tarmac, City, Circuit....go on and on. Put 'gems' on your car for better handling, grip, power, streamlining, etc. Construct special Rally cars by first beating them over and over until you have enough to build your own. Cars 'Armors' existing for 5 parts , the wheels, base, engine, carrosserie, and spoilers.
It would not be the most realistic game but imagine it a bit like the Mario Kart VS Granturismo Crossover...with MH influenced leveling and custimazation.