Just to note: "It’s just that PS rasterizes images when you save them, effectively making the vector tools pretty useless."
That line is bull. If you save as .psd (which, really, you shouldn't save a work in progress as anything else in PS), the vectors are saved as vectors. PS *displays* vectors as raster, meaning that if you zoom in it looks pixelated but that's just how the image would look as a raster at that resolution. Upscale the image and the vectors are re-drawn without quality loss.