I use AI a lot, I work in AI, I find it very helpful and it speeds up my work a lot. But I’ve never found it useful for drafting messages. The AI only knows what you’ve provided as context, and a lot of your own context is only in your head - previous interactions with this person, what your goals are. I think the message should be roughly the same length as a prompt to create the message. Other than that, what do you need the LLM for? You can add a couple of sentences of cruft faster than the AI.