This paper presents a novel design framework for large-area, high-numerical-aperture, freeform metasurfaces. The approach combines the simplicity and fabricability of conventional design paradigms with the extended capabilities of freeform optimization. The design leverages nonlocal interactions between simply shaped nanostructures on an irregular lattice to produce high-order hybridized modes that support customizable large angle scattering profiles. The method is applied to design and experimentally demonstrate multifunctional super-dispersive metalenses and high numerical aperture radial metalenses capable of diffraction-limited focusing and the generation of donut-shaped point spread functions. The concept is also extended to metadevices for the generation and high-numerical-aperture focusing of vortex beams. The design principle involves dividing the wavefront profile into wavelength-scale "super-pixel" regions, within which gradient-based optimization is used to tailor the geometry, position, and orientation of nanoscale elements. This approach enables the creation of devices with high performance, high numerical aperture, and multifunctionality. The results show that the proposed method can achieve efficient off-axis focusing with minimal spurious diffraction and high-quality focusing with reduced diffraction. The paper also discusses the potential applications of the concept in super-resolution microscopy, particle trapping, additive manufacturing, and metrology. The design methodology is validated through simulations and experiments, demonstrating the effectiveness of the approach in achieving the desired optical performance. The study highlights the potential of the proposed framework for a wide range of applications, including microscopy, spectroscopy, and structural light illumination, where large-angle beam deflection is critical for superior performance.This paper presents a novel design framework for large-area, high-numerical-aperture, freeform metasurfaces. The approach combines the simplicity and fabricability of conventional design paradigms with the extended capabilities of freeform optimization. The design leverages nonlocal interactions between simply shaped nanostructures on an irregular lattice to produce high-order hybridized modes that support customizable large angle scattering profiles. The method is applied to design and experimentally demonstrate multifunctional super-dispersive metalenses and high numerical aperture radial metalenses capable of diffraction-limited focusing and the generation of donut-shaped point spread functions. The concept is also extended to metadevices for the generation and high-numerical-aperture focusing of vortex beams. The design principle involves dividing the wavefront profile into wavelength-scale "super-pixel" regions, within which gradient-based optimization is used to tailor the geometry, position, and orientation of nanoscale elements. This approach enables the creation of devices with high performance, high numerical aperture, and multifunctionality. The results show that the proposed method can achieve efficient off-axis focusing with minimal spurious diffraction and high-quality focusing with reduced diffraction. The paper also discusses the potential applications of the concept in super-resolution microscopy, particle trapping, additive manufacturing, and metrology. The design methodology is validated through simulations and experiments, demonstrating the effectiveness of the approach in achieving the desired optical performance. The study highlights the potential of the proposed framework for a wide range of applications, including microscopy, spectroscopy, and structural light illumination, where large-angle beam deflection is critical for superior performance.