Here are some tutorials from the forum and Youtube that could help.
Ratchets:
Our experience with Ratchet Mechanisms in Change Up (62X)
VEX Ratchet Tutorial
315G Ratchets Explained (6 motor drive, 2 motors for everything else)
Smallest vex ratchet
Differentials:
Vex Differentials Explained
Differential transmission - power takeoff from the drivetrain motors
Differentials —“Some help from my fellow SCA member”
Differential Concept
Please share some examples to understand Differential & Bevel Gear Pack use case for vexiq