What design patterns would you implement on the design below to make it more reusable and extensive?

So I've been given the below UML diagram to study for an assessment tomorrow. We will get a diagram similar to this one and we are required to provide a redesign and refactoring of the design above that provides maximum reusability and extensibility, without introducing repetitive code.

What would you change or add (such as inheritance etc) to this and why? I would love to get a programmers view of it!