Okay, got some things I had in my head out of the way so I can focus on this more. I think overall the problem with esca is how slow it is while lacking prio. It's bulk is good but not good enough to handle Kyu + X IMO. On the other hand, Metagross can work in a similar way except that it trades the cool bug STAB for Bullet Punch which means that no matter how weak it is it can still keep Kyu-B in line. Slowbro can be a problem but it can run Thunderpunch/Trick and the fact that it is taking chunks out of it could make things easier for CB Terrakion. What do you think?
Sorry, I'm on trying to do multiple things so I can't really give you as good a response as I would like. It looks like Esca can check everything and serve as the sturdy counter to Kyu-B that we need. However, I'm worried about it being easy to force out as well as being able to handle Raikou AND Kyu-B. Seeing as both threaten our team, having them both together can mean that one removes our check for the other. It may be worthwhile, though.
I know, it's really annoying how random stuff like this can be so bothersome. A lot of trouble would be off our shoulders if Zapdos had a means to beat boosting special attackers (phazing or status) but then Zapdos would struggle against Spikers or Lando-I. I'm going to keep digging, there must be something we can use.