High-performance　piezoelectric　materials　are　essential　for　diverse　electromechanical　devices,　from　actuators　to　sensors　and　transducers.　Here,　we　synthesized　Ce2O3-doped　Pb(Mg1/3Nb2/3)O3-0.29PbTiO3　(xCe-PMNT29)　solid　solutions　via　conventional　solid-state　methods.　In　the　x　=　2.5　%　modified　composition,　we　achieved　a　notable　electrostrain-hysteresis　trade-off,　enhancing　electrostrain　(0.2　%),　equivalent　piezoelectric　coefficient　d33*　(1701　pm　V–1　at　3　kV　cm–1),　and　reducing　strain　hysteresis　to　8.1　%.　Additionally,　direct　high-temperature　piezoelectric　characterizations　revealed　real-time　variations　in　piezoelectric　coefficient　(d33)　and　the　actual　depolarization　temperature,　with　d33　reaching　859　pC　N−1　at　53　°C　and　planar　electromechanical　coupling　coefficient　(kp)　exceeding　70　%　within　30−85　°C.　Leveraging　x-ray　diffraction　(XRD)　and　piezoelectric　force　microscopy　(PFM),　we　elucidated　synergistic　effects　between　complex　nanodomains　and　local　structural　heterogeneity,　enhancing　piezoelectric　activity.　This　study　presents　a　promising　approach　for　improving　electromechanical　performance　and　electrostrain　in　ferroelectrics,　with　significant　potential　for　practical　piezoelectric　applications.　©　2024　Elsevier　Ltd