Well, let's see...I'm presuming this is based on a pair of Intellijel 7U cases joined by the Joiners.
First up, there were a number of modules in this that just didn't fit or make a lot of sense. For example, using the AJH Mini Mod when, fact is, you can get the same general functionality out of adding Intellijel's Noise Tools tile + the Quantum Rainbow that was already in there, and save money in the process. I also chucked out the extra buffered mults (not necessary...you really only need the one, up by the VCOs; the rest can be UNbuffered inlines), the force sensor and the tandem I/O tile.
Also, Maths stayed as well as the PanMix...I'll explain why when I get to those...
Top tile row: MIDI interface added here, using the cab's USB port for the DAW connection. Then the buffered mult and Zeroscope, followed by the QuadrATT. After that, there's one of the two Dual VCAs, primarily for controlling output levels to or from the Panharmonium, then I also put in an FX send/return with an extra pair of jacks.
Top 3U row: The little white sliver is a Konstant Labs PWRcheckr, which gives you some visual indications of your DC rails' health while operating. Then the next thing is Shakmat's SumDif CV adder/subtractor for tinkering with CVs directed toward the oscillators. Then your Cs-L and Odessa, followed by the Quad VCA...and then, the XPan. What this pair does NOW is that it provides a number of CV-controlled stereo ins and outs that feed the stereo input of the Panharmonium, allowing you to generate a stereo mix to that module's stereo input. The XPan also has sufficient inputs to allow a "backflow path" from your mixing section below BACK to the oscillator row.
Second 3U row: A Plankton ENVF got added to provide an envelope follower for one channel of the Stereo In below. After that is the Quantum Rainbow 2, which can feed all sorts of noise signals to various points, but which is mainly for providing a more complex noise source for the Intellijel Noise Tools if needed. Poti/Batumi, Contour1, Qx/Quadrax...and then I took care of the ADSR needs with a Xaoc Zadar + its expander; this is, in fact, what happened to the Instruo ADSR gen, as it made very little sense to have only ONE EG in the same space that could be occupied by a far more capable QUAD EG instead. Following this are your main timbral modifiers: Evolution, Blades, and the dual LPG.
Lower tile row: The Input module is here, then Noise Tools to provide S&H, slew, clocking, etc. After that is Ritual's Pointeuse, which is a bidirectional CVable switch. Next is the other QuadrATT, then an Intellijel Stereo Mix...added to allow you to manually sum the Arbhar, Magneto, as well as other stereo signals back into your main mix, as if you had a stereo return on the PanMix (which it doesn't have, but which this tile DOES take care of). Another Dual VCA then provides either levels for this, or for other modules inputting into the mixing chain. And the Output is last here.
Third 3U row: Modulation fun...Sloths first, then the Morph4 for global-ish modulation processing. But I also put in a Frap 321 for this, which can make for a useful "internal" modulation modifier/mixer for just the Maths, or for anything mod-wise. Right after this is a dual VCA from After Later, based on the Veils VCA design, which again provides CVable level control and/or mixing for your modulation signals. Then Maths...and all of the stuff before, I should note, are there to REALLY complicate what Maths is capable of. That's one thing people overlook about Maths; since it's billed as a "be-all, do-all", most people don't always consider modifiers for it...but when you DO, and when you set things up right, Maths can REALLY shine. So, between the left side of Row 2 and this end of Row 3, plus the extra widgets, NOW this has a serious modulation section, VERY capable of outputting some very complex voltage curves! After this, your Arbhar and Magneto are located above the PanMix and below the output stereo submixer.
Bottom 3U row: There's the second cab's PWRchekr, then Pam's. But after Pam's, there's several modules that optimize what your Plog is capable of turning out. The 2 hp thing is a clock counter which ticks off 1-8 (actually, 1-7, as your thruputted pulse is always the "0"). After this, you've got a 1-in 4-out clock delay, then a probabilistic clock skip for adding semi-randomized clock "dropouts". And all of that provides more complex signals for the Plog to chew on, so that IT can output lots of potential rearrangements of your clocking. I also put the dual comparator and that Ladik Derivator next to the Plog so that they can input their gates to the Plog as well. Both sequencers are next, and they're followed by the Harmonaig and Shifty for quantization and arabesque processing. Then the PanMix returns...and here's why: First of all, this NEEDS a proper stereo mixer with panning and with VCAs at the output stage. Secondly, the XPan just doesn't do this in the "right" way, as it's mainly designed for stereo input/output situations, and some of what you'll be mixing is mono...ergo, panning (with CV control) is pretty useful. And having your final VCAs in the final mixer is a great way to combine functionalities to save space AND up the build's potential.
This isn't TOO much more complex than your initial design...but I put in quite a bit of "sneaky" functionality that, if and when it's needed, can take this to another level altogether. Much of this is going on in the modulation sections in rows 2 and 3; adding the 321 as a "pre-processor" to feed a composite modulation signal in with the Morph 4's processing of other signals just adds mod signal complexity...plus you also have that dual VCA/mixer in that slot. By adding these, the modulation really gets kicked up to another level by just 12 hp of panel space. And there's several points in the build where that sort of sneak happens...so even though this primarily uses most of your present modules as well as the ones indicated in the second speculative build, there's little bits here and there that synergize in that sort of manner. In the end, there's not all that much ADDED...but what was added really stitches the whole build together.