Fun article! I think cyclists are great ultralighters at heart, and we've got a "weight weenie" population that makes the BPL jokes about drilling toothbrushes all the more hilarious for those of us that have seen, or made, drilled-out chainrings, cogs and brake lever or paid obscene amounts to save a few grams (and get it in 3d purple).
I love the singlespeed conversion. Nicely done and it looks like you've fully realized what our multi-speed only compatriots can't see as anything but crazy: it's funnerer on an SS!
Ryan, I suggest you check out the weight savings AND reliability you can get by converting your wheels to tubeless, most likely by using the "Stan's method". Essentially, you'll seal off the rims by replacing the rim strip with some packing tape, ditch most of the inner tube and replace it with some fiber-laden, latex "bullet proof tire" sauce right out of Nixon's limo. You will save a few grams by eliminating the tube, net after adding the "sauce", you'll save even more because you will only need one spare tube as a conservative backup.
In fact, you'll get way less flats and, after you learn your limits on low tire pressure (ie how far is too far), you'll have an extremely reliable system that shaves weight and works better.
I haven't gone over the fully-rigid cliff yet (ie returned to fully rigid) and I can't quite stomach the idea of adding pack weight and racks to my beloved 69'er SS (100mm of Maverick American up front). Articles like this, and the stuff in Scouting about "bikepacking" do have me thinking about putting some cargo capacity on the an old boinger bike though.