That'a right, I'd strongly advise it. I'd get both passport and passport card.
Passport -> get "large" book, same price, but more pages just in case. It's not larger in dimentions, just has more pages for visas, stamps etc.
Passport card -> can also be used for proving citizenship. Same size as Green Card. Not so useful for travel (only few places you can use it), but can be helpful if you lose passport and or naturalization certificate.
Good luck