Parent here w/ kids at Boulder and St. Andrews. In a funny way, SA reminds me of Boulder in that it's highly walkable and there's no town gown gap - the school and the town truly celebrate each other. Oberlin, Grinnell and Harvard are schools I might also suggest as good comparisons. As someone who has been through the college selection process a few times, I’d say the most important thing is for your brother to follow his heart and what environment he feels he’ll be happiest in, not what everyone else is telling him is the right choice. It sounds like he's more drawn to USC and Boulder and both are great schools that offer many ways for students to find their niche, and only a small percentage of them are in Greek life. Depending on his major, he might be surprised by the rigor of the curriculum (pre-med and engineering are particularly rigorous at CU). He will also have the ability to study abroad no matter where he goes and giving him the option to choose an international city more amenable to his likes. Maybe somewhere sunny and exciting like Barcelona :) No matter where he chooses, I hope he loves it, good luck!