Thanks for all the valuable feedback. I did 3 yrs at an Ivy, and one year at the “jewel in the crown” CUNY. Honestly, 90% of the people in my classes at the CUNY did not belong in college, as far as I could tell. BUT… none of those classes were premed classes. Then a little later wound up doing the premeds at the Ivy, post-bac, and they were very challenging, just like everything else at the Ivy. I went to a mid-tier med school, and found that there were quite a few people there who had done well at far less demanding undergrad schools, and gotten in. But I can definitely see the point that a post bac year at local state U would be a lot less suspicious than deliberately taking all premeds at local state college in the summers.
As for double majoring in other areas, medical schools love people who have humanities majors, and college, especially at a T20 school, is the time to take all those amazing classes with incredible professors, and explore interests. I see nothing wrong with using college as time to become well-educated in humanities, and do the pre-meds outside of the time spent at that T20.
But I’d forgotten that there are more specific forums on other sites with people who have been through it very recently.