Careful with your module depths, tho...the 4ms pods max out at 34mm, which significantly limits your possible modules. For example, a good Maths substitute in 4hp less space would be a pair of Doepfer A-171-2s, but at 60mm depth there's no way they'd fit. The Maths, at 24mm, may in fact be the right way to go here. Let's see...(pause)...OK, this:
60 hp 4ms Pod: Konstant Labs power checker, then a Bastl Hendrickson for an input, which allows you to crossfade with the output on the module. This means that you can use the Hendrickson's 1/4" output as a "clean" channel to your amp and crossfading allows you to control your wet/dry levels, either manually or via CV. An Erica PICO RND gives you a sine/pulse LFO, clock (plus clock in from an external sync), noise and random signals and one of two sample and holds, and next to that a Doepfer A-184-1 contains the other S&H, plus a ring mod and a slew limiter to 'smooth' your S&H shifts. Maths next, then I opted for an Eventide Euro DDL for massive delay flexibility, including looping, reverse delays, tap tempo (and the Euro DDL can also serve as your master clock, clocking the PICO RND) and CV over time, feedback, delay mix and an internal LPF. Following that is something very guitar-nifty, and that's a 3-band EQ with CV over frequency on each band. Coupled with the Maths, this will allow loads of timbral shifty weirdness. The CIAO! output allows you to run the EQ in either series or parallel, since it has dual stereo ins. Oh, and a headphone amp, too. Now, this doesn't exactly address things like reverb, etc for stereo operation, nor does this deal with the depth issue I mentioned...but I really intended this more as an example of what's possible in that tight a cab which you can work off of as a basis for ideas.
Wow, thank you Lugia for your extremely detailed explanations and your effort! This is absolutely inspiring, it is much more than I had tested in my modular grid rack. Need to wrap my head around it now. I know that I really need stereo delay and am thinking if a more multi effect with all these mod sources, but it‘s a great start!