If the stone is the first point of contact, then you've got a problem. In bottom heat scenarios, forum members have spent countless hours finding ways to bounce the heat away from the stone and up and around to the top of the pizza. Unless you're using very thick/poorly conductive materials such as firebrick, this is generally the only way to achieve a balanced bake.
Speaking of heat balance, a huge part of the top heat equation is the infrared radiation coming down from the ceiling of the oven. Infrared is distance dependent. The farther from the pizza, the less impact. A high dome, such as yours, only compounds the heat imbalance issue caused by a bottom heat source/lack of deflection. In a bottom heat scenario, the tallest you want the ceiling to be is 4", max. Every inch further away from that and you're losing precious top browning ability.
I have some experience with making a homemade pizza oven that fits inside a Weber Genesis gas grill. I'm quoting Scott's reply above because I believe he's spot on. I totally support his notion of a 4" max ceiling height and his point about getting the heat to flow around the stone in order to get the desired top browning of the pizza.
Theideman, your craftsmanship, welding, and design is fantastic, but as soon as I saw the height of the ceiling, I was thinking that's way too tall. I say leave it as it is if it serves a dual purpose of bread making, but consider adding a track where you could slide in a second lower ceiling which would sit about 4 inches above the stone.
I can't tell from the current photos, but also make sure there is ample air flow on all 4 sides of the stone. This might also require that you have a front door that would close during the bake to ensure more even air (heat) flow flowing at the front of the stone. See my pic below. I accomplish the same thing by closing the lid of my Weber Grill during the bake.
Great project! Fantastic craftsmanship!
EDIT: I just re-read your post and I see your oven is wood fired. My comments above are more for a oven where the heat source is underneath the stone. Could you please clarify how your heat source fits into your design.