OP: You need to do some research on each of these schools as Grinnell, for example, has certainly been the subject of a great deal of criticism regarding the community and the “social life”. The most prominent piece was written by a long time Grinnell professor several years ago and, after garnering a great deal of national attention, seems to have been scrubbed.
Applicants to small, isolated schools should visit each school if feasible. Encourage your son to communicate directly with current and former students if possible.
But, disregarding both negative & positive impressions of others, one really needs to fit when considering small, rural, isolated schools.