Hey Brad looking good brother. The thigh ammo belt is fine, optimal would be equal positioning, but it's not a requirement. I know a lot of builders like to center the ammo box with cover strip thinking logically that's where it should be placed however, as seen in the following reference photo's it can be in either location. Evenly distributing the mounting location on the thigh undoubtedly offsets the ammo belt for the thigh on most armors. That said, it's already mounted so pick your poison, drill new holes and reposition it or leave it as is. Choice is yours. Neither way should effect any level of approval.
As for the chest plate return edge, again here's a reference photo. Except for the sniper knee return edge is not a requirement anywhere so trim as needed.
Hope this helps