Cloth diapers have certainly come a long way from what our parents and grandparents have used.
However, the tried and true flats and prefolds still prevail over modern cloth diapers. They would need a waterproof or water resistant cover, though.
An All-in-One cloth diaper is popular because of its similarity in use to single use throwaway diapers.
Pocket cloth diapers are loved because of their ease of washing and drying and ability to increase or decrease absorbency.
All-in-Two cloth diapers became popular because parents could reuse the cover (waterproof outer shell) several times before washing. The same concept can be applied with simple prefolds/flats and covers.