I am a product of public schools and two state colleges. I saw tons of professors that used their personal feelings of a student to determine their grade. Sometimes this would work in the students favor, sometimes it would work against the student. Until no professors are doing that (I would say from my experience over half are) there absolutely needs to be anonymous reporting on faculty.
What you are advocating for it a system where professors can do anything they want and them simply blackball the student who makes a legitimate complaint and have all their professor friends do the same.