There are plenty of off the shelf sinks that would be large enough for your 12 or 14 in fry pan. In our last coach I removed the existing one, opened the hole a bit and installed a stainless sink from Home Depot or Lowes and updated the faucet and added in Insta-Hot. Wife fell in love with the Insta-Hot option and the sink was plenty large enough for everything you describe.
I'm just saying it's not like you needed to put this kind of extreme effort into a sink to get one large enough but we all enjoy the wood working seminar you have presented. I do have concerns about the longevity of your sink unless you have some additional plans to support the bottom.
