If your boot time was bad before and decent now, this is not thanks to the goodness of systemd but rather the badness of whatever hideous system your distro was using before, and/or because your distro is starting a bunch of useless junk that shouldn't be running in the first place. I've been using flat /etc/rc (all commands in one file, & at the end of anything non-essential) for years (decades?) now, and have always had a login prompt faster than the display can synchronize to the video mode change.
