I confess. I did laugh. However, it's pretty much the design of the burley barns in West Virginia. It provides protection from sun and rain. Depending on your average humidity during curing season, the open ventilation may or may not need to be closed off with some plastic sheeting.
It looks like there is enough floor space to hang 300 plants. Green tobacco weighs a lot (check the Growers' FAQ for some numbers). Make sure you rig a method of suspension that can bear the weight. There don't appear to be very many studs in there, so you may have to add some structural support--especially if you plan on doing any stalk harvesting. 1/8" braided nylon rope, tied to carriage bolts in the studs, can support green stalks across the width of the shed. Primed leaf weighs a lot less.
Bob