I’m required to teach DSA in Java, so I lay down a couple rules early in the course that prohibit 95% of the nonsense garbage that unconstrained OOP allows. Granted, neither of these rules is original or novel, but they are rarely acknowledged in educational settings:

1. All public methods must implement an interface, no exceptions. 2. The super implementation must be called if overriding a non-abstract method.

The end result of strict adherence to these rules is basically that every feature will look like a GoF design pattern. True creative freedom emerges through constraints, because the only allowable designs are the ones that are proven to be maximally extensible and composable.