The state of the art in nitrogen-vacancy (NV) center-based stimulated emission depletion (STED) microscopy has tremendously pushed the boundaries of super-resolution imaging and quantum sensing. Using the exceptional photostability and spin-based optical properties of NV centers within diamond, scientists have reached spatial resolutions of less than 10 nm and enabled simultaneous nanoscale imaging with quantum sensing of magnetic, electric and thermal fields. This review assesses three major innovations, which are pulsed STED approaches that reduce background noise by controlling the time-course of the NV center fluorescence, functional nanodiamonds that enable biocompatible super-resolution imaging of living organisms and optimized spectral excitation-depletion protocols that increase resolution without increasing photo damage. We analytically examine the following existing constraints such as high depletion laser requirements and problems to meet sufficient signal-to-noise and also survey new methods such as quantum technology and machine learning tools targeting at increasing the imaging performance. The synergistic combination of NV-STED with other techniques like atomic force microscopy as well as its application in such areas as neuroscience, cellular thermometry, and the study of quantum materials is discussed. Beyond the latest advances in NV-STED microscopy, this review provides a glimpse into the future of how such technology can develop.