Oven-Controlled Crystal Oscillators (OCXOs) have long been regarded as the gold standard for frequency stability, delivering ppb-level stability required in timing-critical applications. However, their traditionally high power consumption and bulky thermal control systems limit their use in modern power- and size-constrained domains such as unmanned aerial/underwater vehicles (UAVs), drones, portable instrumentation, and long-term test and measurement platforms that operate without continuous power access. This paper presents the design, optimization, and performance evaluation of a next-generation low-power, low-profile OCXO architecture that addresses these constraints while maintaining excellent frequency stability and phase noise performance. Reducing OCXO power consumption poses several technical challenges. The largest contributor is the oven control loop, which maintains the crystal at a constant elevated temperature above ambient to minimize frequency drift. Lowering heater power without compromising temperature uniformity demands a rethinking of oven design, including advanced thermal insulation materials, minimal thermal mass enclosures, and adaptive temperature control algorithms. At the same time, the crystal’s cut, drive level, and aging characteristics must be optimized for stable operation over a reduced thermal gradient. Achieving this balance requires co-design of the crystal blank and oven controller. The performance demonstrates superior warm-up characteristics (<3 minutes to stability) and a profile height below 7 mm, making it compatible with airborne and handheld systems. Applications extend to timing references for UAV/UUV navigation payloads, autonomous sensor nodes, and portable test instruments used in field environments lacking stable power sources. The example provides a possibility of future OCXO miniaturization, offering a practical pathway toward ultra-low-power precision timing in edge and mobile systems.