An update for those who may have been interested in this decision. I have decided to go with Wharton. The admit weekends definitely helped the decision - I really felt at home among current students and fellow admits at Wharton. And though I met a lot of people at Columbia whom I liked, I ultimately found Wharton to be a better fit.
And for those who are interested whether or not or if the fellowship was factored into my decision, I actually asked to be reconsidered for a fellowship at Wharton (it's something that everyone can do) and I ended up receiving a fellowship. So it does/can happen! Really, I had nothing to lose by asking.
Thank you to everyone for their comments and input on this decision!
I love a story with a happy ending.