-Norman is, by far, the best English teacher I’ve ever had.
-Norman is, by far, the best English teacher I’ve had so far.
-Norman is, by far, the best English teacher ever
-Norman is the best English teacher I could have by far
-Norman is, by far, the best English teacher I’ve been able to get
-Norman is, by far, the best English teacher I could ever have
-Norman is, by far, the best English teacher I could have ever had