Goodness. Well, that answers the question of how they were going to get all of SM7a, 7b and 8 released in the West in a timely fashion without an overlarge set: they're not, it's just going to be good ol' application of force.
Judging by this and Celestial Storm, it seems like sets of this size will probably continue to be the trend as we stream towards the end of the Sun and Moon block, assuming Japan keeps pumping out Xa and Xb side sets to go with each of their SM(X) main sets. Obviously it's too early to make any solid predictions, but I wouldn't be entirely surprised if we go through the rest of SM without a set under 160 cards. In the same vein, I'm also expecting us to get another special set on the side... These cards will all have to go somewhere.