Others answered but I want to agree with them, 2 sq ft of floor space isn't enough unless they are confined to the coop
ONLY at night when they are sleeping. My 12 are in 120 sq ft and there is NOTHING on the floor other than 2 legs for the roosts. And they have 27' of roost but they don't use even half of it when it is cold
Figure MINIMUM 1 foot of roost per bird. They'll squeeze closer in the winter but they should have space in the summer since they can't take their down coats off. Mine are out
every day until they go to bed at sundown though the coop isn't usually opened until 8 or 9 AM. I would potentially go as far as a dozen more in the coop but not more than that and then only because they are never confined to the coop. I don't think I'd take much advice from the lady at the feed store.
I have a divided nest box with three 12x12 nests and a 4' community box. Again, as others said, they seem to have their personal favorite nests and that is a PITA. I have pine shavings in the nest boxes (very clean) and on the floor (deep litter). I wouldn't use sawdust, much to fine and, well, DUSTY.
Not sure what "defines" an olive egger. My EE that lays green ranges from mint to olive. I would guess that, at the least, an OE would have to lay olive ALL the time.
Nope, not "official". I wonder if there may be an APA designation some day though since "Araucana/Ameraucana X whatever" mutts are so popular. They just won't be able to have a list of acceptable colors.
Bruce