Here is my opinion after reading your comments. I think that you seem to prefer Brown but very much like Vanderbilt. There is no issue of anti-semitism on the Vanderbilt campus to reassure you. My son’s best friend just graduated from Vanderbilt, and was the President of one of the Jewish fraternity. The only problem that he had was actually leaving Vandy and Nashville because he loved it so much. Both are excellent schools with high powered academics and opportunities that many can only dream of. You can not go wrong though there are no guaranteed admits to either of these places even for the best and brightest.
Early Decision is like a marriage - you are going to the altar with that college. If you are unsure, then you should not be applying ED. Maybe it would be best to apply to your whole list, and see where the chips fall. Often times, what a person is 100% sure of in the fall of their senior year changes by the time admissions roll around in March. My son had his heart set on Northwestern for a number of years - school, location, and program. By the time March rolled around, he was hoping that he did not get in so he could attend another school that he realized was a better fit during the course of senior year (this is where he attended and just graduated from). Maybe you should give yourself that time.