Mutts:
The issue in our climate is that metal is hot in summer and cold in winter. So leaving bare metal walls and roofs exposed to the interior is going to cause you problems, although when you look around at Craigslist, etc. and see all the commercial made chicken houses made in our area, most have metal siding. I don't think of them as bad people, but more like they have not done their homework. They like it because it is cheap, durable, fast to build and looks good. But I doubt any of them have spent the night in one during the winter when it's -10F and blowing like stink outside. Or some day in summer when it's 95F outside and 110F inside. The deal is metal is a great conductor of heat....meaning it radiates heat in when it's hot, and radiates it from inside to outside when it's cold.
You can help that somewhat if you at least line the interior of the shed with OSB to isolate the metal from the birds, and hopefully install at least the bubble stuff or even 1/2" of the polyiso board under the roof tin. Insulating all sidewalls and roof with at least 1/2" insulation board would be better.
Of the two, insulation under a metal roof is most critical. Without insulation, a metal roof housing livestock will literally rain inside from condensation of moisture given off by the livestock.....or in our case our birds.