3-4 sq. feet per bird IN COOP especially if you live in a colder area (less outside time) or have production birds (ISAs, Barred Rocks) because they will get bored or aggressive and peck each other to death. My grandfather keeps birds 1 sq. foot each, and I have seen his pecked to death. (He tosses the pecked ones outside the coop and leaves them to die. I now understand why my parents did not associate with these people.)
A run should have at least 10 sq feet per bird, if you don't want it to turn into a muddy/scratched mess. It also lowers stress.
I feed my adults twice a day. Chicks and younger birds should have more access to feed.
Food and water inside the coop is fine. I live in a rainy area, and I don't have a covered run. It works. They won't spill it during the night, (Chickens can't see in the dark, and they have no desire to go walking around in the dark) but it will attract rodents and predators, so I never leave feed overnight. The water can evaporate and cause moisture problems if your coop isn't well-ventilated.
1 sq. foot per bird only really works if the birds are de-beaked so that they can't kill each other due to the stress of being crowded like that. This is especially true at point of lay, 18-30 weeks, which is when the laying hormones go wild, and they're most likely to kill each other.
And can we see a picture of the dead rooster? Are the feathers all missing in a patch? Is there a lot of blood? Anything that looks like tooth marks? Are any other chickens missing feathers?
(I'm thinking that they might have been pecking at each other due to size constraints, but that a sickness killed him off, since you don't mention any blood. When chickens kill each other, they do it messily.)