On the assumption that you are using the Gold Medal Better for Bread flour and the Textbook flour Measurement Method, I did some calculations and used the expanded dough calculating tool at http://www.pizzamaking.com/expanded_calculator.html
to convert the recipe you used to baker's percent format, as follows:
|Bread Flour (100%):|
Olive Oil (2.42562%):
|556.56 g | 19.63 oz | 1.23 lbs|
354.89 g | 12.52 oz | 0.78 lbs
1.89 g | 0.07 oz | 0 lbs | 0.5 tsp | 0.17 tbsp
13.95 g | 0.49 oz | 0.03 lbs | 2.5 tsp | 0.83 tbsp
13.5 g | 0.48 oz | 0.03 lbs | 3 tsp | 1 tbsp
940.79 g | 33.18 oz | 2.07 lbs | TF = N/A
Since you have been making four 12" pizzas with the above amount of dough (33.18 ounces), each dough ball weighs about 8.3 ounces. For a 12" pizza, I calculated a corresponding thickness factor of 0.073354. This value confirms that your pizza crusts are on the very thin side. But, to be honest, I don't see anything out of order in either the recipe or how you have practiced it. Inherently, with a hydration of around 64%, the dough should not be on the dry side. And, with about 2.5% oil, the dough should be easy to handle. These values should translate into a crust with decent oven spring and a chewy crust with a soft crumb. Unless you used a lot of bench flour or a lot of flour on your peel, it is hard to see how you ended up with a very dry crust with a lot of uncooked flour.
If I were to suggest something at this point, it might be to make a few test pizzas with a thicker crust. For example, if you divided the dough batch into three, such that each dough ball weighs about 11 ounces, and make a 12" pizza with that amount of dough, the corresponding thickness factor becomes 0.089848. That value would correspond to a typical NY style crust thickness. That might yield a softer and less dry crust.
As another possible explanation for your problem, maybe you have been baking your pizzas for too long, even at the lower oven temperatures, and that has led to dry crusts as the moisture in the dough evaporates. Remember, you have been making some very thin pizzas. Given the very thin pizzas you have been making, I would think that the higher oven temperature and a short bake time would produce the best results, with a less dry crust but a reasonably soft center. If that hasn't worked, then you might try making some test pizzas with a thicker crust as mentioned above.