External spinal cord stimulation devices, and associated systems and methods. A representative system includes an external signal generator having a housing with a peripheral edge and a recess extending inwardly and along the peripheral edge. The recess can be positioned to releasably receive an elongated portion of an implantable signal delivery device. The system can further comprise electrical signal generation circuitry carried within the housing, a power source carried within the housing and coupled to the electrical signal generation circuitry, and at least one output terminal electrically coupled to the electrical signal generation circuitry and coupleable to the implantable electrical signal delivery device.