It is absolutely worth it. I was admitted with an unweighted gpa somewhere between a 3.6-3.7. I applied ED. If UChicago is your dream school and you put time into your essays and try to show them you belong there. Wanting to go to UChicago already tells me that you have a good chance at fitting in. 30 years ago the admit rate was much higher. Not because it was easier to get in, but because it was so self selecting that there were fewer applicants. UChicago can see past your grades if there is more to you than just a GPA.