x2, that is a very good place for ventilation for your build. Pretty much could open up everything from the cleanout door all the way up to the roofline for ventilation. Really amazing overhang!I'd open up a large vent under the roof overhang in front.
1 sqft of venting per bird is a pretty good rule of thumb.
The current vents you have are by my estimate barely sufficient for 2 birds, and that's only if they're left open.
Just to check, what did you finish the floor with? Paint?We didn’t put linoleum on the floor since it’s too slippery.