Oh, I have been there with all my kids. First, make sure you don’t pass your concerns along to your child. At our school, switching teacher assignments almost never happens. This may sound like bad news but I have found that there have been several years I’ve gotten myself all worked up about a teacher and then by the end of the year realized that it was a great fit and that my child grew from the experience. Keep in mind that teachers see a different side of our kids at school and they put a lot of time into forming class groups. They don’t always get it right… but I kind of feel like it’s part of life and kids need to learn to deal with all kinds of people, including teachers.
Couldn't agree more with both of your first suggestions. 1. Don't poson the well with your child. Telling your child to expect problems makes them quite likely and creates a built-in excuse. 2. A whole variety of teachers is a lot like life, where one has a whole variety of bosses and co-workers and friends and acquaintances.
Doesn't mean a parent/child needs to put up with abuse, certainly, but there is value in a student adapting and struggling and making it through.