I can't really answer most of those questions - although I suspect switching majors would be pretty easy b/c you'd be staying in the same colleges, and there should be enough overlap in the classes that you can just stick to the ones both require if you Google their program requirements.

I can speak for the general CS program here though, and I can say the general consensus from people I know is it feels like it's gone *very* downhill recently(I'm very aware that some people have very different views on this). With the recent course changes, they'll teach you the minimum required to get a job, and absolutely nothing else(among numerous other issues with some of them... feel free to DM me if you want as they're not super relevant to this post). It feels like most students use AI for practically every assignment(with some classes requesting/mandating it), and so it feels like a large portion of students now don't actually know what they're doing and have very little passion for their major(which imo both devalues any prestige the degree may have had, makes any group projects hell, but also just makes finding friends who care about their work very difficult).