> It can be a real pain to read code like this if it's overdone
wherein (4) is, when things start getting complicated, a way to end up avoiding things turning into closure soup. Also being able to selectively override things with inheritance can really help factor things out and clean things up.
> at some point it doesn't seem like overkill anymore.
Though I suspect "at that point, ask yourself if you're overengineering it and only if you're sure you aren't consider moving to a class" definitely applies :)