Looking for big schools that look at applicants activities/leadership

This would (generally) describe many less selective schools especially public schools…including nearly the entire SEC (the conference you noted in your OP). Note in the SEC there are several schools that require test scores: U Tenn, UF, UGA.

Private schools and highly rejective publics tend to be relatively more holistic. Sticking with the SEC, Vandy values leadership and ECs, but they also value test scores (and stats/rigor > ECs/leadership), plus they aren’t ‘big’.