I'm not getting this at all. So, this is a pair of Rackbrutes. But the bottom 6U may just as well be a Minibrute 2S. And since that's a cheaper alternative, then why not just use a Minibrute 2S? A smarter move would be to not put the Boog in the cab in the first place, since it already has its own cab and that cab already has power. Use your Eurorack space for things that NEED the housing and power instead.
Garfield's right about the envelopes, also...there's not really any proper ones there. Ripping out the Boog will give you back 70 hp (a RIDICULOUS amount of space for any module to take up, fyi) and that should allow for proper EGs, attenuverters (you want to be able to invert envelopes...a big "win" with VCFs, especially) and all of the other bits that need to be there. Oh, and about that Antiphon...you do realize that it's a DIY module and also has a 150 mm reverb tank that will require space inside that Rackbrute for mounting, right? If that hadn't occurred to you, it might also be a candidate for removal, as it's yet another ginormous module in a little cab, which is always a bad idea.