As has been said, you need to know at least a bit of everything, and enough to be considered an expert in most things. You don't necessarily have to have to be able to do everything, but you certainly have to know well how it's done.

You'll be leading whole teams who will be looking to you for support and structure on the projects. You'll be helping production bid projects, so you need to have a good, realistic idea of how long everything takes.

This all just takes experience. You can get it at small studios or big studios, big projects or small projects. But you gotta get your hands in everything and learn.

And you gotta develop leadership skills. Positive reinforcement, morale-building, coordination, management. You've also got to learn how to non-emotionally correct people who aren't getting you what you need, whether artists or production or management.

Good luck!