Simulations using the Control-Oriented Transport SIMulator (COTSIM) and DIII-D experiments have been carried out to demonstrate the performance of a novel integrated-control architecture for simultaneous regulation of individual-scalar magnitudes. The individual scalars considered in this work include kinetic variables, such as the thermal stored-energy or volume-average toroidal rotation, and magnetic variables such as the safety factor profile at different spatial locations. Separate control algorithms have been designed independently for each of these individual variables that use robust, nonlinear control techniques. In addition, the individual-scalar controllers have been integrated with Neoclassical Tearing-Mode (NTM) suppression algorithms, supervisory and exception handling algorithms, and an actuator manager, both within COTSIM and in the Plasma Control System (PCS) of the DIII-D tokamak. The resulting architecture has a high level of integration and some of the functionalities that will be required to fulfill the advanced-control requirements anticipated for ITER. Initial simulations using COTSIM suggest that the plasma performance and its Magneto-HydroDynamic (MHD) stability may be improved under integrated feedback control. These simulation results also show good qualitative agreement with DIII-D experimental results in the steady-state high-$q_{min}$ scenario, which is one of the candidates for steady-state operation in ITER. By means of individual-scalar feedback-control techniques in conjunction with NTM-suppression techniques, the confinement deterioration caused by NTMs in these scenarios may be significantly ameliorated.