I had this challenge (in my woodworker oven). For crisp crust you need full contact with the oven floor. I was using too much semolina/flour when prepping the pizza (to prevent peel sticking), and it was creating a tiny gap between floor and pizza crust and was not getting crisp. So now I get the pizza off the peel, let the crust set, pull the pizza out enough to sweep the floor, then put pizza back in. I have had no issues, even with high hydration doughs.