In my opinion, in the end it won’t really matter what actual decision you make in the end. If you are a person with a positive attitude, you will look back at your decision and focus on all the reasons why that decision was the right one and be thrilled with the outcomes and your life. If you chose the private school, you will think about the great experiences there, the friendships, the class interactions, etc. If it UW, then you will think about the money you saved, the great friends you made, the great classes you had there etc
If on the other hand you are a person who is generally an “Eyore”, then you will always look back and wonder if you made the right decision and second guess it every time something challenging happens. So if class sizes are huge, you will wonder, if a professor is not giving you enough time, you will wonder, if you don’t get the right job after graduating from UChicago, you will look at the debt and wonder.
Don’t listen to anybody here, figure out what kind of person you are first. That should tell you how you will view this decision in 10-20 years, no matter what you decide. I know that is kind of philosophical, but most decisions in life are not binary.