In various embodiments, a stylization subsystem automatically modifies a three-dimensional (3D) object design. In operation, the stylization subsystem generates a simplified quad mesh based on an input triangle mesh that represents the 3D object design, a preferred orientation associated with at least a portion of the input triangle mesh, and mesh complexity constraint(s). The stylization subsystem then converts the simplified quad mesh to a simplified T-spline. Subsequently, the stylization subsystem creases one or more of edges included in the simplified T-spline to generate a stylized T-spline. Notably, the stylized T-spline represents a stylized design that is more convergent with the preferred orientation(s) than the 3D object design. Advantageously, relative to prior art approaches, the stylization subsystem can more efficiently modify the 3D object design to improve overall aesthetics and manufacturability.