Maybe I can give some advice that will help you in your design. I have a friend who is an independent patenting agent and we have had many conversations about the plumbing industry. I have seen a number of widgets that have been patented, prototyped and produced for the plumbing world. When a plumber like me has a service call and discovers one of these items attached to a toilet supply, fill valve, overflow, ect. we focus on it as the reason for the service call. No problems existed before the attachment or purchase and after a short period of time the troubles start to show up. Upon removal of the appurtenance, life goes back to normal.
So my advice is this. Be sure the item is time tested and true to its function. Be sure it does not contribute to or create a new problem. If there is no practical need for it, the plumbing community is not likely to welcome or purchase it...it becomes an added expense and just another thing to break/leak and cost us all more money. Use durable materials and go above the minimum specs on design, early failure of a product will put it into a grave fast. (We all remember what happened to polybutylene epoxy when exposed to chlorinated water).
If you can find a plumber to test and critique the prototype, do so with non-disclosures signed, of course. We can be great cynics, but also will praise without bias.
If you are successful, we would all love to see a new product that continues to push the plumbing industry through the 21st century.