We present a study on the influence of different scan and reconstruction parameters on the image quality of the differential phase signals obtained from speckle-based X-ray phase-contrast imaging measurements in single-shot as well as 2D and 1D speckle-stepping modes. In particular, the effects of the analysis window size and the number of diffuser steps on the spatial resolution and signal sensitivity of images of a phantom sample are investigated and discussed. It is shown that the trade-off between spatial resolution, scan time and simplicity of the setup has to carefully be addressed for each specific experiment.