What do mature college guys look for in girls? (BE HONEST)?

All of the above and none of the above. Reliability, honesty, willingness to accept the world without blaming others for your own misfortunes, willingness to accept the consequences of your own conduct, willingness to avoid judgments of self and others, sense of humor, ability to focus on life, enjoyment of life, variety of interests. These are far more important than body size, hair color, eye color, bosom size.