I think Universal should make its own Mario Kart-style kart racing game. It should use the two-characters-in-one-kart mechanic used in Mario Kart: Double Dash and Cartoon Network Racing for the PS2, because it's kind of a shame that mechanic hasn't been used more often in racing games. Here's my idea for who could be in the launch roster (with more characters possibly coming to the game as post-launch updates/DLC):
The Fast and the Furious
Dominic Toretto
Shrek
Shrek
Donkey
Princess Fiona
Puss in Boots
Back to the Future
Doc Brown
Marty McFly
Jurassic Park/World
Dr. Ian Malcolm
Owen Grady
Blue
Despicable Me
Gru
Kevin, Stuart, and Bob/The Minions (race as one character)
The Office
Michael Scott
Dwight Schrute
The Secret Life of Pets
Max
Gidget
Snowball
The Grinch (2018)
The Grinch
Madagascar
Alex
Gloria
Skipper
King Julien
Kung Fu Panda
Po
Tigress
Monsters vs. Aliens
Susan Murphy
B.O.B.
How to Train Your Dragon
Hiccup
Toothless
Astrid
The Croods
Eep
Guy
Trolls
Poppy
Branch
Queen Barb
The Boss Baby
Boss Baby
She-Ra: Princess of Power (1985)
She-Ra
The Munsters
Herman Munster
Knight Rider
Michael Knight
The A-Team
B. A. Baracus
E.T. The Extra-Terrestrial
E.T.
Woody Woodpecker and Friends
Woody Woodpecker
An American Tail
Fievel
The Super Mario Bros. Movie (exclusive to Nintendo consoles)
Mario
Bowser
As for the different karts the characters could drive, I think some of them should be based on famous vehicles from the different franchises represented in the game, like Dominic Toretto's 1970 Dodge Charger, the DeLorean time machine, KITT from Knight Rider, and the A-Team van.
Let me know what you think about this idea, and what characters/vehicles/tracks/franchises you would like to see in the game!