HIM is Darius, or is manipulating Darius in some way
HIM wanted the Rowdy Ruff Boys back in Townsville, so he used Darius, the rising star of JS Inc. to send them there. Mitch's dad will have been or is part of JS Inc.
Honestly, I have no idea why I say this. I suppose it's because his dad was mentioned a few times and I was wondering if he was important to the plot. Mrs. Morbucks will have something to do with Him
I have found Mrs. Morbucks to be both really kind and just a little creepy. Little hints like her blackmailing Brick and being in contact with JS Inc. Brick will get the power he always wanted but discovers it's Lonely at the Top
Or he gets everything he wanted ala Dr. Horrible's Sing-Along Blog-style alienating Blossom somehow. This is more a hunch based on some things the author has stated in her trivia and a/n on her live journal and perhaps some foreshadowing. Brick is very focused on his future and the goals he has set for himself and his brothers. I get the feeling that Boomer won't want to be part of that plan anymore now that he's with Bubbles. Butch...well theoretically by the story comes to this point he'll be starting to change because he's with Buttercup. Or alternatively, he's by his brother's side for a short while at JS INC before figuring out it's not really what he wants and leaves much to Brick's rage. Either way the main thing is that he'll get all this power and realize it doesn't mean shit without Blossom, because that's what he really wants and what he really cares about anymore. Bonus points if something went down between them before he comes into power like a kiss or a really big fight that borders on Love Confession. Even more bonus points if Him somehow has a hand in the success of Brick's plans and rising to take over the company. Mrs. Morbucks is the head of PRM
Or some sort of valuable employee. Towards the end of chapter 5 Mrs. Morbucks asks Brick to keep in mind PRM's wishes to form a partnership with JS Inc when he goes back to the company. PRM is explained as being basically the European equivalent to JS Inc. Mrs. Morbucks lives in France, and it would certainly explain all her connections, especially with people like Reccardi. It makes sense that she would ask Brick to keep in mind PRM when he goes back to the company, because it seems to be widely believe and implied he'll be calling the shots in the future. Brick will not rejoin JS, Inc., but will start his own organization
Reccardi expressed the desire to work with Brick personally, not JS, Inc. Penny mentioned many influential clients of JS continually ask after the Boys and won't accept substitutes, and also that other field operatives miss them. Joseph also seems to have an interest in Brick alone, not in JS. It's possible that, instead of taking John Smith down physically (maybe due to some influence from Blossom), Brick sets himself up as a rival to JS, Inc., and takes his revenge by taking clients.