The rotary chemical looping combustion reactor design - which utilizes oxygen carriers in a matrix of micro channels for indirect fuel conversion - provides a viable path for fossil-based electric power generation with CO2 capture. Its thermally integrated matrix of micro channels minimizes irreversibilities associated with heat transfer in the reactor, and establishes multiscale coupling between oxygen carrier kinetics, reactor geometry and plant operating conditions. In this study, we implement an optimization framework that exploits this multiscale coupling for simultaneous reactor design and power plant economic optimization. Results for the methane-fueled power plant reveal optimized thermal efficiencies of 54-56% for a rotary chemical looping recuperative Brayton cycle plant, with compressor pressure ratio in the 3-7 range. By switching from an efficiency to an economic objective, we identified solutions that reduced electricity cost by about 11%; by performing scaling and technology maturity projections, we show competitive economics for the rotary chemical looping plant with CO2 capture.