THE GRAVITY RECOVERY AND CLIMATE EXPERIMENT (GRACE) LAUNCHED IN 2002 HAS BEEN PROVIDING INVALUABLE INFORMATION ON THE EARTH'S TIME-VARYING GRAVITY FIELD AND THE NEXT MISSION GRACE FOLLOW-ON WILL CONTINUE THIS TIME SERIES. AS PART OF THIS PROPOSAL WE FOCUS ON ARCHITECTURES OF FUTURE POST-GRACE-FO LIKE MISSIONS. SINGLE PAIRS OF SATELLITES LIKE GRACE AND GRACE-FO ARE INHERENTLY LIMITED IN THEIR SPATIOTEMPORAL COVERAGE. FULL GLOBAL COVERAGE FOR A SINGLE PAIR CAN TAKE UP TO 30 DAYS FOR SPATIAL RESOLUTIONS OF A FEW HUNDRED KILOMETERS THUS A SINGLE SATELLITE PAIR IS UNABLE TO OBSERVE SUB-MONTHLY SIGNALS IN THE EARTH'S TIME-VARYING GRAVITY FIELD (E.G. ICE SIGNALS HYDROLOGIC SIGNALS OCEAN TIDES ETC.). SMALL SATELLITE SYSTEMS ARE BECOMING INCREASINGLY AFFORDABLE AND WILL SOON ALLOW A CONSTELLATION OF GRACE-TYPE SATELLITES TO BE DEPLOYED WITH THE CAPABILITY TO RANGE BETWEEN MULTIPLE SATELLITES. HERE USING SIMULATION STUDIES WE WILL INVESTIGATE THE PERFORMANCE OF SUCH A CONSTELLATION FOR DIFFERENT NUMBERS OF SATELLITES (N) AND DIFFERENT ORBITAL CONFIGURATIONS IN ORDER TO UNDERSTAND THE IMPROVED PERFORMANCE THAT MIGHT BE GAINED FROM SUCH FUTURE MISSION ARCHITECTURES.