You can completely use a linear ratio. Google any world class chef's recommendations, they will all recommend a fixed ratio e.g.: https://www.masterclass.com/a

You can completely use a linear ratio. Google any world class chef's recommendations, they will all recommend a fixed ratio e.g.: https://www.masterclass.com/articles/how-to-cook-the-perfect-basmati-rice#what-is-the-difference-between-long-medium-and-short-grain-rice https://www.masterclass.com/articles/how-to-cook-the-perfect... Rice cooker instructions also use a liner ratio. Cooking rice isn't rocket science.