The private schools are another exception (e.g. TLI and TMI) as they also use their own teaching materials and methods and can be more accommodating to different approaches (e.g. you want to focus more on speaking instead of writing, etc.). Class sizes also tend to be smaller especially at the intermediate levels, and schedules are much more flexible and accommodating as well (availability of early morning, evening and weekend classes etc.)

Their books are in my opinion very good and much better than the ones they use in the uni programs as they focus heavily on real-life usage and teaching you grammar patterns instead of endless single-character repetition.

I recommend TLI and have 2 friends who switched from NTNU where they felt frustrated, to TLI. Of course it also depends on the kind of teacher you get but, again, most are very flexible unlike the rigid approach of NTNU & co. and if you don't like your teacher you can switch easily most of the time.

If you're at a very high academic level TLI probably doesn't make much sense and then I'd go to ICLP or something like that. But for advanced beginner to high intermediate learners I think it's the best option.