Bon travail. I've focused on reading French books and have made surprisingly fast progress considering my complete failure at learning languages in high school.

IMHO, the differences between spoken French and written French are overrated for a number of reasons.

Reading helps you develop your vocabulary quicker than any other method because you see new words and phrases used in specific contexts rather than being defined outside any context, any people tend to learn best from examples rather than from definitions.

It's a great feeling finishing a book and it's even better when you finish a native French book and even even better when you finish a native French book for which there is no English translation.