Lets take a look at a couple of things, Why would the crust be tough and rubbery? Ans: Either too much protein in the flour you are using or insufficient fermentation for the type of flour that you're using. For your process I would say that a flour with not more than 12% protein content should be sufficient. You might even be able to drop down into the 11% protein range. Examples of this type of flour are; 12% protein: General Mills Washburn's, Full Strength or Superlative. 11% protein: H&R Bread & Pizza, King Wheat, Doughbuilder, and GM-44. By using one of these lower protein content flours your should be able to use your short fermentation time without creating a tough, chewy finished crust. As for the failure of the crust to rise during baking, this can be partially related to an overly strong dough that resists expansion/oven spring during baking, again, going to a lower protein flour should help. The fact that you are blending the salt and sugar together might also impair the yeasts ability to function in a normal manner, so I would suggest adding the yeast separately. If it is IDY or compressed yeast it does NOT need to be suspended in water before addition. For your operation I think a better dough management process would be to mix the dough to a fixed time (say 15-minutes in low speed) as it is not recommended that you mix a dough to temperature as you will never know what the level of dough development is. Adjust the water temperature to give you the finished dough temperature you are targeting (*I'm thinking 70F water should be about right), then after scaling and balling, allow the dough balls to set out at room temperature for 30-minutes before taking them to the cooler. For a dough of your size, it should not take more than about 15 to 20-minutes to completely scale and ball. For a one day dough such as you are using times and temperatures are more critical than they are with a dough that will reside in the cooler for 24-hours or more.
Tom Lehmann/The Dough Doctor