For me, im going low poly, textures 64×64 (mostly), fog for distance stuff, some shader magic to get a blur effect and CRT lines. Other than that I'm not worrying much. My camera is smooth, I'm sure my sound effects aren't going to sound like they're from the n64 either, and my character animations are pretty fluid. Some of that will break the n64 vibe, but I'm okay with that. I'm not much of an animator.