I can tell you set up is fairly new.... no poo on your ramp.
I have the same type but am planning to switch to something that will let the poo fall through, because it builds pretty fast with almost 50 chickens.
They probably do need some more places to hide. For younger chicks I just put a cardboard box or two. Some shrubbery, even in planters maybe?
I've had tarp flapping before and even though it was startling at first when it got windy, it just became part of their norm before long.
Since you get snow, I am sure the clear roof will be beneficial and I can see you aren't afraid to use a tarp. So you probably won't have any issue coming up with shade when you need to for summer.
Do you spend any time out there?
I can't tell how your ventilation is on that. Since you live in the snow you probably already know how important it is to have good ventilation to avoid frost bite.
And the other thing I suggest is keeping some debris on the ground. Like leaves or compost. I see you have some hay. It's my understanding that bare ground won't have enough beneficial bacteria in it to keep disease down. Some people use a deep litter method to provide a little extra warmth in their coops. I live in the PNW and deep litter doesn't work for me because it's too wet all the time everything grows mold.
How do you keep your goats out of your chicken grain?