This work investigates the synapse response under the identical gate pulse stimulation scheme for Hf02-based ferroelectric FETs (FeFETs) with 2D channel using calibrated Monte-Carlo simulations with the nucleation-limited switching model. Our study suggests that a larger effective activation field (Ea) and a narrower spread in the distribution of Ea should be engineered to achieve a better conductance response for the FeFET synapse. In addition, adequately increasing the thickness of the interfacial layer and the ferroelectric layer of the FeFET may facilitate the accumulative switching and improve the synapse response. Besides, we have shown that it is possible to tune the conductance response by back-gating, and an adequately applied negative back-gate bias may result in better linearity and symmetry. Our study may provide insights for the FeFET synapse design crucial to the accuracy and performance of neuromorphic computing.