If you consider yourself a free-thinking, creative person, then why wouldn’t you want to mix it up with many different kinds of people? If a liberal arts college has good academics, generous financial aid, and national market reach, then it ought to be able to attract a variety of tribes (including yours). As far as I know, admission committees aren’t screening kids for their political beliefs or taste in music.
However, if you really want to avoid the kind of students you seem to be describing, look at the percentage who join Greek societies. Although … this probably isn’t a perfect indicator (for instance, I suspect MIT frat culture is different from W&L frat culture).
http://colleges.usnews.rankingsandreviews.com/best-colleges/rankings/most-frats