My D is at junior at Tufts and couldn’t be happier. Loves it for the reasons you do. I believe the undergraduate experience is at least as much (if not more) about fit and feel as it is about reputation. My D has felt “validated” beyond her expectations. A TA in her freshman year encouraged her to become a Writing Fellow. Her lab advisor urged her to apply as a Summer Scholar and Goldwater Fellow. Both her advisors (yes, she has two–an embarrassment of riches by virtue of an accommodating department head and a personally invested professor) are there with info on grad programs, internships, course options. She could tell you more, but I’m passing this along as a proud Jumbo parent.
And FWIW, my D got chatty a year or two ago with a Harvard grad student while on a train home. The student told her outright that a number of STEM courses at Tufts were more challenging than comparable ones at Harvard (indeed, Tufts kids are known to take Harvard’s orgo class as it is supposedly easier than at Tufts), so the argument that “Tufts is not academically up to par with UPenn and Harvard” is a complicated one. There is no grade inflation at Tufts. There is competition, but I’ve never heard my D complain about it being cutthroat or dog-eat-dog. I think high school was worse on that score!
You might want to read this article about Harvard students’ reputation for not attending classes.
https://newrepublic.com/article/119321/harvard-ivy-league-should-judge-students-standardized-tests
Good luck!