Personal essays can make a difference. You hear lots of story’s about admissions. Who know’s how true they ar. Here is one based on a formula: sat+gpa+random multplier= floor to making the min base cut. This number changes each year. Then they look at your writing.
If demographic’s wasn’t a factor in admissions like they say, then why collect it during this phase? Collect it after acceptance.
One AdCom ( admissions counselor ) at a different school told me they could fill the freshman class with all valedictorians. But they want a diverse and ‘interesting’ class.
They have a good point and it would seem you get that data from the extra curriculars and creative writing.
I would suggest having you kid get good at writing 500 word essays. That is a paragraph. They are not taught how to get right to the point in a few words.