I’ve been building a game using some of the things that I’ve learned here from the various Gamedev.tv Udemy courses. I occasionally thought that the classes used in some of the courses were overly simplified. After spending a couple hundred hours developing my own project I have an observation.
Keeping the classes simple will save(would have saved 
) a whole lot of headaches in the long run. When you have to refactor (and you will have to refactor, many, many times), it’s much easier to change a small class with simple functionality than it is to change a huge very complex class.