what should my coop look like in regard to feeders perches, and nesting boxes?

Id give them 1 more nesting box...they may all decide to use just one, but an option would be good.
As for perches, have one at the highest spot possible, and maybe another one halfway down so they can get up easier. make sure u dont have a perch right under enother one, the poop tends to fall and one of ur chickens could be in the danger zone.
I keep my feeder outside, but it doesnt really matter. just make sure the feeder/waterer is raised off the ground....especially the waterer

 

We have 2 boxes for 6 hens...even though they all use the same one. Most seem to prefer to share so if you have one for about every 3 or 4 birds, I'm sure they'll be just fine.

We have two perches...well, they get into the rafters as well, so I reckon it's really 3, LOL. We offer a 2 x 4 on it's side so they can flat foot it if they want, and a tree branch that's about 2 inches diameter, so they can clutch if they prefer. Our coop is really too small for them to fly, so we built a little ladder they can climb to get up there YN is right..don't have anything at all under the perch or it'll get pooped on...including food, water, nesting boxes or other birds LOL.

We keep the food and water outside...we prefer that they only go in the coop to sleep and to lay. Come winter, we'll probably have to have some inside as well so they don't HAVE to come out in the really cold weather, but we don't get a lot of that, so it will just occur on a day to day basis. We close the coop after they've all gone to bed and open it at first light, so they have access to everything all day long.