Feedback: Typing on default values.

Just some initial feedback. I wonder if there is any way to say if I have defaults and I enforce defaults if it can never be `type | null` in the typing. I find myself doing ! alot. I get that a param is totally optional and could be null if a user removes it, I'm guessing this where enforce defaults comes into play. It would be nice if I could say which params have to have a default enforced.