Here's my take on the system based around one Manis Iteritas.
An output module might be a good choice... but I'm assuming you'll take care of that outside of the rack.
I thought about sneaking in a logic module or some noise. Maybe an attenuverter.
But you can't have everything in 80HP
Some highlights:
A MIDI interface in case you want to use this with your DAW.
Effects via the Pico DSP and possibly the Disting Mk4
A dual VCA.. because you need them.
A Temps Utile and Ornaments & Crime. That will give you a ton of useful features and internal sequencing.
A master clock
Dedicated distortion... because if it isn't distorting, you're doing something wrong.
A Disting... so you won't get bored trying new things.
A second mixer because you might want to mix some CV or use the mixer as an attenuator.
Find Ricky Tinez on Youtube and follow him. He's great with small skiffs. But a word of caution, small skiffs are much HARDER to plan than larger systems. Space is critical, the size of modules can lead to cramped spaces to get your fingers into once everything is patched up. You might want to use longer patch cables to they lie flat or flatter and get out of your way.