I am also concerned that the OP’s hesitancy re: CalTech’s rigor might mean that it is not the correct school for them – especially if they need to maintain a high GPA for possible medschool.
OP, do you have any other acceptances where you would be happy to attend?
Or—there are still some schools with good, automatic merit for high-stats students that are still accepting applications. University of Arizona is one and their deadline to apply for thie coming fall is May 1, 2023.
Also, OP, if the financial aid you were offered at Cornell is so far off from your NPC, please double-check both your NPC data and your FAFSA/CSS Profile data. The award should be close to your NPC unless your parents are divorced, or own a small business, and the NPC didn’t ask about that. If there is a large discrepancy, I recommend that you or your parents contact the financial aid office to ask for a review to determine why there is such a large discrepancy.b