In a professional context I couldn't agree more. However for a hobby project I couldn't disagree more. Implementing safe down-casting (up is trivial), dynamic dispatch, encapsulation, and other OO(ish) features is an absolutely wonderful learning experience. Like most first attempts, it will probably be a mess as you say, but there can be a joy in making a mess of things so long as you're not inflicting it on the unsuspecting.
