Had a bash at this one...
You'll notice that I upped the size of the cab from 84 to 104, and added a tile row. This is designed with an Intellijel 7U x 104 in mind, which helps with a number of things, such as pedal interfacing, power, and so on as well as simply providing more SPACE in which to push the build a bit further. Went ahead and filled it on out, as well.
Oh, crap...what have I done here? Welllllllll....
TOP: Konstant Labs PWRchekr, so you can keep an eye on your DC rails, then a 1 hp blank to help the PWRchekr stand out a bit better and to fill a 1 hp hole, natch. Then, TWO Plaits (since two oscillators allows for a lot more in the way of things such as audio-rate modulation, FM, and so on) which are followed by a Veils. Then that HUGE black thing there is G-Storm's redux of the famous Synton Syrinx filter, which is one of the most expressive VCFs out there. It works on vocal formants (and a bunch of other methods!), so the output has a rather voice-like contour to the timbre...provided you use it that way, as there's a lot of other things it'll do, filter-wise...especially with the expression pedals! Then Rings, Beads...and a Tesseract TexMix setup with four mono ins + the master module. The TexMix gives you VCAs for audio levels per input, dual FX sends and dual stereo returns, panning, your outputs and a headphone preamp.
MIDDLE: Manikk quad freerun LFOs with symmetry control over the square and triangle wave outs. Then Maths, and after that is a Tiptop MISO for manipulating/merging/messing with modulation signals, and a second Veils for VCA control over modulation signals. An Intellijel Quadrax/Qx combo handles basic AR envelopes, but also a bunch of other sorts of mayhem since the Qx can be used as a "cascader" for the EGs there, offering EOR and EOF outs. Then for more "normal" envelopes, a Doepfer A-140-2 Dual ADSR. After that are effects...the Morphagene, a Frequency Central Stasis Leak, giving tap delay, chorus, and reverb and stereoization, and a Happy Nerding FX Aid XL for all of the other onboard FX.
TILES: This is where it gets fun. First up is the stereo input module, which connects to the dual input 1/4" jacks on the cab. Then after that are two expression pedal interfaces, a third that uses a pedal switch to flip between A and B signal paths, and two sets of Intellijel external FX interfaces that let you add two loops of mono I/O pedals to the fray. Then the stereo out, which fixes the output module question as it connects, like the input module, to the output jacks on the cab.
Now, if you know the Intellijel cabs, you'll notice that this is built "upside-down". This is very deliberate, as it brings all of the external 1/4" jacks for pedals, stompboxes, and the synth's I/O plus the power switch close together so that you don't have 1/4" cables hanging all over the modular, and this will make using the pedal complement much easier. So you have to tote it around upside-down...eh, not an issue, really. This build effectively eliminates the original's power supply module, fixing that issue, plus it deals with the audio I/O question AND allows the build to be much more guitar-centric via the tile row's interfaces.