I have 5 schools to suggest to you. All are politically engaged campuses in one way or another. All are in or near state capitols & so have easy access to state politics and possible internships. I don’t know how small is too small, but all are smaller. I’ll list undergrad enrollments in parentheses. Because they’re near state capitols, they’re all near airports as well. All have at least pre-engineering or a dual degree engineering program, leaving that option open to be explored. Varying in levels of admissions competitiveness, the easier ones are more likely to have scholarship opportunities for top students.
Richmond (3200) - A great place for a political nerd to be right now because it’s literally a laboratory in political change. State government at all levels has been flipped from red to blue in just 3 years. Everyone wants to know why. Because she teaches at a Virginia college (Christopher Newport), Rachel Bitecofer has studied this and written about it. Fascinating stuff. A mix of kids from instate and the Northeast insures that both liberal and Conservative voices get heard. Already on your list.
Gettysburg (2400) - A high percent of students majoring in something related to politics. The school’s Eisenhower Institue has an office in DC and prepares students for public policy work and provides mentorships. Clubs run both a Model Congress and a Model Arab League. It’s a politically engaged campus across the spectrum. Even has a libertarian club.
Macalester (2200) - Right in the St. Paul, it’s just half an hour by bike or by bus to the State Capitol. College campuses can get so oppressive these days that they can stifle debate. Macalester recognized this as a problem a few years ago and put policies in place to insure that Conservatices get heard and that there is open dialogue for all points of view.
Union (2200) - When I saw Syracuse on your list, I though Union College was an even better choice in upstate NY. Founded during the George Washington administration, Union has a long history of political engagement starting at the local community level. They also partner with the state legislature and organizations in DC to set students up in summer internships both in Albany and Washington. Union is the rare example of a small LAC with a long established (1845) engineering program, offering majors in Electrical, Mechanical, Biomedical, and Computer Engineering. They also have minors in Environmental Engineering, Energy Studues, and Nanotechnology.
Wesleyan (3000) - Long a liberal bastion, Wesleyan has activist groups for everything. Despite being small, they have a separate College of the Environment and they run their own farm. Woodrow Wilson once coached the debate team which bears his name today. The Wesleyan Political Union holds biweekly discussions on foreign policy and domestic politics. Although their graduate school is small (a few hundred), they offer an interesting 5 year BA/MA program with a research orientation in about 10 disciplines including Math/Computer Science and Physics. They also offer doctorates in both fields as well as a few others.