I'm playing Big Blacephalon next quarter :)
Ok, I honestly think that Exeggutor will be a good deck. By that I mean, it will be a top tier Malamar varient. You just play Magcargo/Zebstrika to get around the discard your hand, and hitting 180 for 3 on a non-gx is very good. Since you'll only be playing draw supporters most of the time post rotation, you won't have to worry about playing a supporter that isn't draw post rotation. You'll be playing 4 custom catcher anyway, which is an instruct if played by itself anyway. I think it has a lot of potential, and I will make a list once the whole set has been revealed.