I Think I Have Enough To Start

You can never have too many shelves. Seriously. Never too many. Ever.
Besides, I want a three shelf unit on the wall next to the door. And I think I have enough leftover wood to build at least one section. Turns out I do. So I’m going to build one. It’ll be 72″ wide by 12″ deep and three of these tall, plus a short base.
I ran the numbers through the sagulator… yes, that’s a real thing. According to the calculator, the eye will notice a deflection of 1/32″ (0.03″) per running foot. My specs say that I’m looking at 0.009″ per foot. That’s without any support in the middle. I may be accused of overbuilding, but they’re strong. The thing is, it might look odd with that distance of open span… Tell me what you think, does it need a middle divider?
So, that’s how I spent my night.