Excellent suggestions in theory, but a hammer and a punch aren't the most precise implements, and from experience I can tell you that attempting to punch centering holes in close proximity to one another is nearly impossible without making a mess of things. Especially if you're starting with a small substrate, like credit-card sized ones I used for my seeds.
With such a small surface it is an almost impossible task or at least for me to have accurate 100 dots. 
I can see a few other ideas to keep our seeds private from community members in the last couple of days but I am asking myself how many people are going to take this risk with their primary wallet seeds? Even with multiple backups, the secret innovative storage of keys or seeds seems risky to me.