I've been wanting a mob that it's literal purpose is to annoy the player. Basically Ogodis are loud mobs that will follow the player when seen. They won't attack just like the phantoms that you all hated. And you don't have a choice but to kill them if you don't want them to ruin your C418 experience. I've thought of having something fun and silly to the game and it's a great addition if you think about it.
...I can see some sort of system like this, but I don't think it necessitates an entirely new mob. Creepers are incredibly annoying despite their lack of sound, the wandering trader somehow manages to get stuck in my base regardless of what I do... etc. Maybe the recently added 'Screaming' goat variant could follow players around on sight. I think this would be amusing, without entirely ruining the player experience. (And, let's be honest, goats are just evil as it is.)