Wish I had pictures for you, but I'm in progress of a build towards a similar end: it's a 8'x16' breeder coop divided into 4'x8' sections with runs for each section that will be a minimum of 4'x20' (so each section can hold a maximum of 8 birds). Right now it's still being framed up though, so I can't say how well it'll work overall. The biggest pain will be all the doors for coop access, I think. I'm going to take what I learn from this and try and build out a revised version next year for a divided grow-out coop to correspond to each breeder pen.
IMO, building the sections attached should save some money overall -- you can share walls so you'll need less materials and you can take advantage of standard lengths to maximize your cost per square foot. Plus your interior dividing walls need only be strong enough to keep the chickens separate, instead of predator proof.