Honestly if you like him that much, I wouldn’t worry about even bringing it up! But I do love your options, option 1 Is great if you see him noticeably struggling to get words out and his stutter is real severe all the time. But other than that, if it doesn’t bother you, why bring it up? My first love (we still keep in touch at age 30 and she has kids but I don’t lol) she noticed I stuttered when we met in 8th grade and I heard her whisper it to one of her friends and I was like “wow fuck you then” lol. But somehow we continued to grow our friendship and eventually into a couple. Not once did she ever mention my stutter and she saw me for me. I’ve had many girlfriends after that and girls I was talking to since, and not one of them ever mentioned it or teased about it, it was always me that brought it up first and most of the time they’d say “I didn’t even notice” or “I noticed but it doesn’t change anything or the way I feel about you” so maybe if you say that to him also, that would make him feel ultra comfortable!