I'm really liking the look of Crabrawler. On the stream, we saw footage of it smacking a lot of the common Pokemon in the official metagame, such as (regular) Kangaskhan, Landorus-T, Cresselia, Smeargle, and Ferrothorn. I'd say that this is a good indicator that it's meant to be anti-metagame; while this in itself is of course awesome, I think it's a deeper indicator that GF is starting to care about their format, which should mean a much more balanced 2017.
Water Compaction is... interesting. It sounds good in theory, but I just don't think it'll work. Unless Sandygast and Pile o' Sand Pallosand have beastly HP and SDef, they're not going to be able to live most Water attacks with enough HP remaining for the Defense boost to matter. At least there's still hope that it'll get Arena Trap as an HA!
Also, the Sandcastles are, in my opinion, the creepiest Ghosts that GF has ever created. The reason is that if you read the Dex entries of the other ones, most of them talk about the terrible things that they apparently do. With Sandygast and Pallosand, presumably these incidents of it possessing people and making them bring it more sand have been seen and documented. That is, they actually happen.
Well played, Game Freak. Well played.
EDIT: Forgot to talk about Turtonator. All I'll say is this:
"BEHOLD, Perry the Platypus! The Turtonator!"