:)
I try to pay attention to people's locations when making suggestions because for me standing under a roof is enough weather protection while tending the birds and a closed storage shed = an oven in summer but I don't have to worry about blowing snow building up on my shoulders or -40 windchill.
Welcome to BYC. Where, in general, are you located? Climate matters, especially for housing.
Storage in the coop is a great idea and protecting the stored items from chicken dust is an even better idea.
One issue I see with your plan is the corner roost bars. That design appeals to a human...