Imaro
Legend
I prefer first person actually. I have no problem with GMs who speak in first person as NPCs (though I don't think it is a requirement of play because I know lots of people who don't like to speak in first person in games and get by just fine). In terms of voices, I tend to find them off putting unless the GM in question has enough charm and charisma to pull them off (not acting chops, but just charm and charisma). My friend Rob is particularly good at this for example and I enjoy his game a lot. But I am fine with any delivery that suits the personality of the GM in question. If I have a GM friend who is naturally very reserved and dry, I don't expect their NPCs to be different than them in voice and tone. Like I said much earlier in this thread: I am not there to judge peoples' performances. I don't see it as the GM needing to do all these things to impress me. I just want the GM to run the game in a way that feels natural. I find heavy use of narrative descriptions, don't feel very natural to me, can often get very dull and just are not what I am looking for.
I find that interesting since I would say speaking in character is performance/presentation vs. having a natural conversation... wouldn't you? Or do you see it differently?
Also wanted to address the it's not core statements you keep making... perhaps the individual specific examples being presented aren't core... but the fact that at least one is used in most people's game seems to me to lean towards performance/presentation in some way or another being core to most if not all games...