@jmtabb
Have you looked at D3 swim team rankings?
https://www.collegeswimming.com/division/3/teams/
Some schools in the top ~10 may be too small (Kenyon), too selective (MIT), or both (Williams) to meet your “match” and other criteria. Maybe check out Emory and Tufts. Or NYU.
In the next 10, you have the same problem … plus a few more schools that may not have the intellectual atmosphere you want. Down a little farther, at #34, is Case Western (which seems to push the right buttons).
If you’re willing to relax your size/location criteria, the top 40 includes a few other ~match schools that a nerdy athlete might find attractive. Like Kenyon, Bates, Occidental … and maybe Gettysburg, Dennison, or Connecticut College. But those are all LACs.
On paper, Emory, Tufts, NYU, and Case Western would seem to be in your match zone (more or less … without getting into hard-to-measure factors like “demonstrated interest”). If you don’t care so much about the quality of the swim teams, maybe have a look at Rensselaer and Brandeis.