ثُمَّ بِاعْتِبَارِ الْقِرَاءَةِ وَالْكِتَابَةِ يَجُوزُ أَنْ يَكُونَ بَعْضُ السُّوَرِ أَفْضَلَ
In the respect of recitation and writing, some surahs may have greater merit.
A special merit or reward attached to reciting one surah does not render another surah nondivine. Reward for recitation, instructional benefit and divine origin are distinct properties.
For instance, a surah may explain a central point of belief especially clearly and thereby offer a particular educational benefit. Such benefit does not divide the eternal divine attribute into portions of unequal perfection.