You need to look up the history of the Rosary. It was meant to reflect the 150 psalms. Hence, 150 Hail Marys, AKA the "Little Office of the Blessed Virgin Mary," 15 decades, not 20.
Beads were previously used as early as the 7th Century, but it was called the "Psalter of Mary" still including 150 Hail Marys still reflecting the 150 Psalms.
Don't you see how this is corrupting what was already there, totally taking out the meaning of the entire exercise?
Plus, how more obvious can you get to call them the "Luminous Mysteries?"