In a laser module (310), single-emitter laser diode chips (110) are positioned at different heights on opposite sides of the module's combined output beam (114). Each laser diode chip (110), and its corresponding fast and slow axis collimators (130, 134), and turning mirror (140) are positioned on a corresponding heat-dissipating surface region (340). High thermal stability and output power are obtained in some embodiments even if the modules are combined to obtain higher-level modules (310-2). Other features and embodiments are also provided.