Requirements

A portable, high performance machine
Performance is defined as plug-and-play stability, and high print quality, in all materials
Uses high temperature, 3 mm extruder, opimized for both fast printing (E3D Volcano Nozzle) as well as flexible filaments (short and supported extrusion distance)
Easy to source parts
3D printable frame that still allows for high stability
Stability of 3D printed frame may be assured via mini rebar plus concrete inside the pipes if needed
8" bed for minimum viable product
extensible to 12" bed after 8" version is optimized
Includes a full Design Guide
Includes a FreeCAD workbench for design.
Has well-developed cable management
Has quick exchange toolheads via magnetic mount and complete unpluggability of print head using a single connector.

Concepts

Double Connector may be used with a 6 or 12-pair cable
Gauge 22 Wire Ampacity is 5A enclosed, so it is suitable. It is 2.5A with 4-6 cores.
DIY Cat5 splitter -[1]