I might as well try to figure the stat distribution out if I can. Keep in mind that the stat values that I'll be bringing up will be integers, with the stat maximum being 24.
I have to first start out with the third image, as the first two images use the Paraglider glider part for Toadette's vehicle combos.
Now, when compared to the Super Glider, the Paraglider lowers weight by 1 point to boost acceleration by 1 point. In fact, the following seems right...
Super Glider, Sail Plane, Waddlewing Glider, Wario Glider
*Acceleration: 0
*Weight: 0
Paraglider, Parachute, Flower Glider, Koopa dako, MKTV Parafoil, Cloud Balloons
*Acceleration: +1
*Weight: -1
It seems that all of Toadette's combos that have their stats visible for the first two images are using the Standard Tires and Paraglider, so I can at least estimate on the stat boosts and drops that the vehicle bodies seem to offer.
Toadette's Standard ATV + Standard Tires + Paraglider
*Speed: 11/24
*Acceleration: 11/24
*Weight: 12/24
*Handling: 15/24
*Off-Road: 19/24
Now, if I were to replace the Paraglider with the Super Glider, the Acceleration would drop to 10/24, while Weight would rise to 13/24.
As for the Bear Rider body, when compared to the Standard ATV, the stat differences are as follows...
*Speed: 0
*Acceleration: +2
*Weight: -2
*Handling: +2
*Off-Road: -2
The Wild Wiggler when compared to the Standard ATV...
*Speed: 0
*Acceleration: +3
*Weight: -3
*Handling: +4
*Off-Road: -4
Next up are the bikes, and I'll start with the Standard Bike body...
Toadette's Standard Bike + Standard Tires + Paraglider
*Speed: 11/24
*Acceleration: 14/24
*Weight: 9/24
*Handling: 19/24
*Off-Road: 15/24
Replace Paraglider with Super Glider, and Acceleration becomes 13/24, while Weight becomes 10/24.
Next up is comparing the Standard Bike to the other bike bodies...
Yoshi Bike
*Speed: 0
*Acceleration: +2
*Weight: 0
*Handling: +1
*Off-Road: -3
Jet Rider
*Speed: 0
*Acceleration: +2
*Weight: 0
*Handling: +1
*Off-Road: -3
Broad Bean
*Speed: -3
*Acceleration: +4
*Weight: -1
*Handling: 0
*Off-Road: +1
Now this seems odd. For some reason, the Broad Bean seems imbalanced, but because the images aren't the best quality, there may be some errors with my work.
Moter Dozer
*Speed: 0
*Acceleration: 0
*Weight: 0
*Handling: 0
*Off-Road: 0
Burning Bowl
*Speed: 0
*Acceleration: 0
*Weight: 0
*Handling: 0
*Off-Road: 0
Wait, so am I to understand that the Moter Dozer and Burning Bowl have the same stat boosts as the Standard Bike? That's rather unusual.
Maximum
*Speed: 0
*Acceleration: -1
*Weight: +1
*Handling: -2
*Off-Road: +2
Mach GP
*Speed: 0
*Acceleration: +2
*Weight: 0
*Handling: +1
*Off-Road: -3
Another Yoshi Bike copycat for the Mach GP.
I wish that I could go further by going through the kart bodies, but without any visible stats for the Standard Kart, I can't really compare the other kart bodies to it.
Edit: I almost forgot about the stats for the following...
Toadette's Bear Rider + Monster + Paraglider
*Speed: 11/24
*Acceleration: 11/24
*Weight: 12/24
*Handling: 14/24
*Off-Road: 20/24
Replace Paraglider with Super Glider, and Acceleration drops to 10/24, while Weight rises to 13/24.
When compared to the Standard Tires, the Monster's stat differences seem to be as follows...
Monster
*Speed: 0
*Acceleration: -2
*Weight: +2
*Handling: -3
*Off-Road: +3
As for the Slick wheels when compared to the Standard Tires...
Slick
*Speed: +2
*Acceleration: -1
*Weight: +1
*Handling: 0
*Off-Road: -4
So the Slick wheels have a stat imbalance, just like in Mario Kart 7.