First -- welcome! Second -- breathe. Denison is test optional, and gives merit awards to test optional kids. Wooster requires scores, but my kid who turned out to be a miserable standardized test taker submitted his scores to Wooster and still got substantial merit award. The beauty of holistic admissions is that it really is holistic -- the whole kid. I think the fact that my kid's portfolio told a story -- from his essay to his recs -- about what kind of kid he was (not at the front of the pack, but a kind, thoughtful person who got along well with all kinds of people) helped with merit. So, for a student who is genuine, and makes the effort to connect, and understand the culture of a school, there are wonderful options. You might also take a look at Earlham, test optional, and just across the Ohio/Indiana border.
The 3000- 10000 undergrad range would rule out most LACs, which is where you are more likely to not have TAs .
If you are willing to go closer to 2000, Denison seems to meet your priorities, at about 25 min from Columbus which is garnering all kinds of recognition as a great smaller city for young professionals. Dickinson might be another option but --- as lovely as I found the Dickinson campus, it is not an enclosed campus and has a town street separating parts of campus, and the gym and fine arts buildings require crossing other streets to get to. Dickinson is about 30 min form Harrisburg -- the PA capital but not a large city.
Conn Coll is enclosed, but not really close enough to large cities (New London doesn't count, I assume).
In response to the question about how important are class visits -- my LAC kid's experience was that visiting classes helped him develop confidence that he belonged at these schools, but I'm not sure that the specific experience on any campus could be generalized to that school as a whole and used to compare across different schools. Like an overnight visit, a class visit can "put off" a student simply because it was a flat day -- the class after a midterm, for instance, when energy might be low.
I second @InigoMontoya's comments about scheduling department visits -- my kid generally set up meetings for both his fine art and music interest, which usually involved tours of the facilities and extended conversations with faculty. That experience helped him see whether, and how, he could see himself at that school. We too were searching for merit, so were not too worried about whether he would get in to his list of schools, more whether the merit would be enough and whether he would flourish at a particular school. Junior Visit days can help streamline some of that, if there are department "open houses" where you can drop in and talk with faculty.
Junior days can be a whirlwind -- our experience was that it was more about pumping up interest among the visitors than about sharing concrete information about the school. I think a regular visit is more useful, though I dragged my kids to a few junior days to get them engaged in the process.
As long as a return visit to interview on campus, or get an alumni interview is feasible, I thought that waiting until my kid was a little more comfortable with the process made sense for interviews. Your mileage may vary!
@civitas -- yes, that is one reason my kid did overnights at some middle of the pack schools, but not the ones we were hoping would be in the final mix. We wanted him to develop the confidence that he was "ready" for this next stage (he could be a bit of a homebody) by having the experience of staying in the dorm, but not at the expense of developing a negative impression of a preferred school based on a particular host.