It was so long ago that the specifics have faded, but I remember I was coached to use a variety of positive responses. "That's a great question," yes, but also things like "I'm glad you brought that up," and "I was hoping someone would ask about that!" It wasn't my cup of tea, too artificial, but the advice was contemplated.

The next question (which is a great one, from what I understand) is: Why do LLMs use these phrases so much if humans rarely use them in written form? Maybe a fair portion of training data comes from lecture transcripts, where such responses are common when responding to direct questions? And/or system prompts are just instructed to be like that?