Hi! As for roosts, most people seem to use either branches or 2x4s. Since you're in Ohio, many recommend using 2x4s with the 4 inch side facing up so birds can cover their feet in the winter and prevent frostbite. With that many birds, a ladder type roost would probably be easiest. Do you have ventilation up high in the eaves? (If not, I highly recommend it!) Make sure your highest roost is 2 feet below those ventilation holes so that breezes don't blow directly on your chickens in the winter. Any lower ventilation that you have should be able to be opened for summer and closed (or partially closed) for winter. Ventilation is SUPER important!!
So, roosts: 2 feet or more below eave ventilation. Also, 12-18 inches from the wall, or your chickens might be pooping on the walls! Roost height can be anywhere from 1 foot above ground to 4 or 5 feet. The important thing is that they are higher than your nesting boxes, or else hens will sleep in the boxes. 2.5-3 feet seems pretty average for roost height, though you can go much higher than that if you don't have heavy breeds. As for nest boxes, if you make them 18+ inches off the ground, your birds can walk under them and you won't lose any floor space.
That's all I can think of for now...hope that helped! Breeds would help us give you more specific feedback for roosts and such.