Curious about how you mentioned cast iron needs the most work to maintain non stick, especially with eggs. I have a cast iron pan that i scrape clean every couple of weeks. I cook 2 eggs in it every morning. Once theres a layer of melted butter i rarely have eggs stick unless i overdo them or have too high of heat. I do get some sticking when i add some ham to the cast but I always put the eggs on one side and the ham on the other so the residue from the ham never impacts the eggs and builds flavor between scraping.