Flexible circuitry is populated with integrated circuitry (ICs), and contacts are distributed along the flexible circuitry to provide connection to an application environment. The flexible circuitry is disposed about a rigid substrate, placing the ICs on one or both sides of the substrate with one or more layers of integrated circuitry on one or both sides of the substrate. The substrate is preferably devised from thermally-conductive materials and one or more thermal spreaders are in thermal contact with at least some of the ICs. Optionally, as an additional thermal management feature, the module may include a high thermal conductivity thermal sink or area that is disposed proximal to higher thermal energy IC devices. In preferred embodiments, extensions from the substrate body or substrate core encourage reduced thermal variations amongst the ICs of the module while providing an enlarged surface for shedding thermal energy from the module.