Is it permissible for the woman's guardian to reject a suitor due to his limited memorization of the Qur'an and Hadith, despite his religiosity and good character?

It is not obligatory for a woman or her guardian to accept a specific man, even if he is pious and knowledgeable, and they have the right to reject a suitor. Not having memorized the Book of Allah is not a reason for rejection, but the guardian should not reject a suitable suitor to avoid discord and spinsterhood, and to facilitate marriage.