I haven't seen anything in regards to this specifically so I wanna know what your main combo in MK8DX is. I do Luigi on either Mr. Scooty, Teddybuggy, and Streetle with either Roller Wheels or Leaf Tires and either Paper Glider, MKTV Parafoil, or Cloud Glider.
I played Mario Kart 8 and Mario Kart 8 Deluxe and when I noticed the names of the staff ghost profiles, they seem to be the same CPU Miis from Wii Sports Club and Wii Party U. Plus, I discovered their nationalities.
Within Mario Kart 8, several courses utilised anti-gravity, which allows for racing on places that normally won't be drivable due to gravity, allowing for more uniquely-designed courses. The mechanic also has the perk in giving a slight boost when racers bump into each other or one of the posts...