Went off on this...first of all, starting with a Mantis as the cab rather than the Rackbrute:
ModularGrid Rack
Rather different architecture from a synthesizer. There's "sources", but you don't deal with them in quite the same way. And the same goes for modules.

TOP: this row is all about the main audio chain. The Monde preamp also contains an envelope follower with both positive AND negative envelope voltages, and the usual trig/gate setup. But this also can handle most anything at the input, given that you have a "combo XLR" there. After this is something just for the guitar: a Frequency Central Thermo Nuclear overdrive/distortion with an actual micro-tube in there. Then Beads for granular tampering, the DLD, and THE filter for something like this, 4ms's Spectral Multiband Resonator. Very stereo, very complex, very wild-sounding in this context. Also note: each of the past three modules also has a dual VCA (Veils architecture) available for outputs for better control over the signal levels going to the mixer. And the mixer is Toppobrillo's Minimix, six channels in (two are stereo) with panning on four, and AUTOpanning on two. And then at the end I put a Happy Nerding Isolator; since we're dealing with a guitar at the input and probably an amp output on the other end, I thought it was VERY important to have some DC and crud elimination at the output so that any groundloops and other crap are shunted by the Isolator's isolation transformers. It's also got your "main" stereo out pot AND the headphone preamp...and there's another on the mixer, also.

BOTTOM: Mostly "helpers" here. The first things are all pedal-related: a pair of ADDAC 301 Floor Controllers gives you a pair of expression pedal inputs, then a pair of the Strymon AA-1s allows stompboxes to be integrated into the signal; note also that there's a VCA pair for one of the two AA-1 outputs. Next, I put in a Temps Utile instead of the Pam's because I think it fits better in this context...where you want some basic sequencing, off-module control, and the like. And after that is the mayhem of the Freq Central Bartos Flur II, which uses all sorts of gates, triggers, CVs to generate trigger/gate patterns of its own. Then you've got a Klavis Mixwitch...a CV-controlled switcher x2 which can shift either CVs or audio between destinations, plus a number of other tricks. Next, four free-run LFOs, then Maths, another VCA pair, and a Klavis Quadigy for four channels of envelopes, and that there is the modulation core...loads of potential, including generative-type control capabilities. And last is the final effect...Uli's knockoff of the Bode Frequency Shifter, which not only makes clangers...but is also the secret to MASSIVE phasing sounds.

So...a little different, but definitely fun AND very usable for live gigs as well as the studio.