This is my first modular synth rack on Tiptop Audio Happy Ending Kit.
Currently I only have left three modules, Plaits, Rings and Marbles.
I also have Moog32, DFAM, 0-coast beside this, and some other synths, microKorg, microbrute, Rocket and Elektron boxes.
I am going to control via Keystep and SQ1. May also connect with Analog four.

The PICO Drums seems like a poor choice to me, especially if you have drums on some of your other devices (like the Elektron gear). It would make a lot more sense to have gone with a PICO DSP so that you can have mono-to-stereo FX as part of the build. This would leave 1 hp (like it does now) which I'd suggest you fill with a Konstant Labs Power Checker...probably the smartest thing anyone can put in a 1 hp 'hole'.

The other thing I'm puzzling over is that if this is in a Happy Ending mounting and not something with a powered cab, where's your power supply?

Lugia> Thank you for your advice. I was intend to use Pico Drum as just tiny sample player not only for drum. Yes, it seems godd idea to replace with DSP for stereo out.
Power supply, I have changed rack configuration and put a uZeus now.