It is wise. The paladin does a lot of hitting with weapons. Only about half of the paladin's spells use the paladin's 8+CHA modifier for saving throws. Many of the Paladin class features use the charisma modifier more directly, but it is still weighted in favor of strength. For example, Oath of Devotion Paladin's can temporarily make their weapon sacred, granting a temporary bonus of their charisma modifier to their weapon's hit rolls. Strength always adds its modifiers to a weapon's hit roll, and for the damage roll too.

Max stat for a PC is 20.