First, I need to record this as a recipe in my account at insight-live.com so it can be printed at any total, documented with pictures of it on different clays, firing schedules and how they affect it, general notes. And be accessible from anywhere with any device. Then I need to start working on improving it. With all that feldspar it is sure to craze, I need to reduce it and substitute the some of K2O it contributes for MgO (from talc). With all that clay (29 total) it is sure to crack while drying, I need to split it into part calcined kaolin and part kaolin (the ball clay is not needed). And those raw colorants: Better to use a black stain. At a minimum it is better to use cobalt oxide than carbonate. The burnt umber could likely be increased to eliminate the need for both the manganese and iron (since it supplies both and has zero LOI).
A downloadable program for Windows, Mac, Linux for doing classic ceramic glaze chemistry. It has been used around the world since the early 1980s.