Teacher RO, city GHBs are a passion & need for me. I've made many for myself and others. Mine are designed to be security check friendly, so no weapons, pry bars or big knives. And mine are made to be worn, to & from work/play. Commuter kits. The article you link, when read with its comments, are an excellent template. I added my 2 cents in an additional comment, posted today, to your linked article. Happy building.