You could always use a dowel plate. Lie Nielsen sells them or you can make one in a short time with many sizes
AH!I had the exact same situation as Jim Creasmen above. I'm making two Southern cellarettes right now with bellflowers and progressively smaller dots below each one. I use carving chisels for the odd sizes that are not covered with my standard plug cutter set. The dots are only 1/8 thick so the carving chisels work fine. Interestingly, I do have a 1/8 inch plug cutter in my set - it's very old and no idea where I got it.
I posted some tutorials on Instagram: Login • Instagram