Four swivel casters at the corners of the cart.

Benefit: The cart can be moved in any direction without the need for turning around.
Drawback: The cart can be hard to control when moving in a straight line. Easy fix: Equip the casters with swivel locks.

An easy fix to this is to equip the industrial casters with swivel locks. Then when the cart needs to be moved or towed in a straight line, the rear casters can be locked.