Option 1.
Well worth it. Like, even if I never had any experiences with some of these characters (by which I mean everyone but Byleth), I still found it nice to actually, you know, be receiving these extra characters, because the more the merrier right? They're all pretty fun in their own ways and they come with some nice stages too.
What a good pass. And ending it with Byleth was, to me, the cherry on top of the cake, if the other DLC is the icing, especially when it came to the reveal itself, I was bursting out laughing.