Value/message/actor/event oriented programming like you mentioned is useful for building distributed systems. I am a huge fan of going a step further and learning this model:

Imperative shell, functional core.

The external shell of code in a project is responsible for network connections, console IO, etc. But the internal guts of a program should be largely functional, that is, instead of mutating (changing) values, consider returning different forms of the same value.

Decisions (branches, logic) are made at one level, data dependencies at another.

The talk Boundaries by Gary Bernhardt describes this model in detail: https://www.destroyallsoftware.com/talks/boundaries