I would suggest stepping down in protein content to address the toughness issue, then you have two options to achieve a more open crumb structure in the dough skin. Option #1 is to include 2 to 3% WRISE (fat encapsulated chemical leavening) in the dough formula. Option #2 is to allow the pressed skins to proof a little prior to going into the freezer. Begin with a 2-minute proofing time and incrementally increase the time until you find what you are looking for. An easy way to do this experimentally is to pull a few skins off of the line and set them aside for a predetermined amount of time, then freeze and hold to replicate a real world experience, then prepare into pizzas by whatever method you elect to use, after baking, allow pizzas to cool for 5-minutes, then using a very sharp serrated blade knife, invert the pizza and cut the pizza in half, turn on edge and compare the crumb structure to that of a pizza made using your normal process.
While two minutes may not seem like a long time, when using a press with a heated head and platten, it can make a very significant difference in the volume/height of the finished crust after baking while creating a more open, porous crumb structure.
Tom Lehmann/The Dough Doctor