FWIW, we would like to have the ability to show the current state of the value that the control represents. However there are major technical hurdles to that, because in many cases Dorico only calculates the optimal value for the property at the time the score is laid out, and it may change depending on the context (eg deleting nearby notes may cause the casting off to change).
One thing I forgot to mention earlier is that these controls are not options, they are properties. That may seem like a minor semantic point but the key thing is that a note (or other item) only has properties for the things the user wishes to override. If the slider isn’t ‘on’ that means that the property doesn’t exist and Dorico will calculate an appropriate value on the fly.