Okay, so......looking at this picture above, see that tray that's filled with wood chips on the RIGHT SIDE? That is already partially set up for a great roost bar/poop tray setup right there in front of you. Take and clean out that tray (te one on the right) and replace with some Sweet PDZ...
Yes, more ventilation for sure! I'd put small ventilation windows up under the peaks of your roof line front and back at the very least.
WOW!! What a dramatic change already...bravo! Now that you've taken those dividers out of those right-side nesting boxes, do you realize you have the...
If you need any help figuring out that roost/poop tray setup, give me a holler. I should be home from church by noon or so. Don't be alarmed by the price on the PDZ. It is a bit expensive, but it lasts forEVER. Plus it makes your coop smell real good, too!
Great! This way your roost/poop tray setup will be "facing the nesting boxes" on opposite sides of the walls. You should probably move your nesting boxes down to where they are no more than 12" off the floor. Slap up a 1 x 6 across the bottom front of the boxes, too....gives them a bit more...
Sorry to say....it's the coop. That roost bar is way too small for your birds! What I would do is first get rid of that set of nesting boxes on the right side entirely. The remaining nest boxes are more than sufficient. Then build yourself a proper roost, which includes using a 2 x 4 laying FLAT...