1000000%. I really am not a fan when someone is rejected, and in a file review/adcom meeting/whatever, they are told to do that school's master's program. I truly do not understand the point of those beyond more income for the school - they are not useful career-wise. At all. They also are in no way guaranteed to make you a more competitive applicant or get you a seat in a class.
FWIW, I have had a vet school tell me I had absolutely no chance and shouldn't bother. Twice. Things are verrrry different now with Michigan State. I hear they no longer have a steady stream of prevets leaving the admissions office in tears

The admissions counselor that was there for many years was absolutely brutal.
You can figure this out on your own, though. Break out your calculator!
For the bolded - that information is usually on the schools' websites. If it's not, then I would email/call/whatever them again, because how they approach repeated courses will absolutely affect your decision to repeat a course. There are definitely instances where it's not worth it.
You're absolutely correct with this - based on what we can tell (as in, we aren't on adcoms), internal GPA cutoffs are higher than ever at most/all schools. So yes, you do literally need a high enough GPA to even be looked at.
This is a huge thing I want to point out. You did not change your academic stats, but picked different schools, got better letters, wrote better essays, and got better experience and you are already seeing this pay off. Grades are absolutely very important, we know this, but the importance of everything else is underestimated I think. If these components weren't that important, they wouldn't be required. When you compare it to the GRE, which rarely held significant value in the admissions process...well, many schools have done away with this requirement by now.