More space is always better.
Always help to have places 'out of line of sight' for new birds to 'hide'....good to put feed and water there too.
But adding new birds as chicks is the easiest, IMO, once you have a brooding area set up...
If egg production is your game, then you might want to plan on having a brooding area right in the coop. Integrating little chicks is far easier than adding them when older. You'll want to add new birds early each year if you want winter eggs.
Gonna be hard to manage the poop from 80 chickens.
That would be a lot of cardboard to change out every day or three(I imagine the odor would get yah after that long).
I love my poop boards, sifted daily poop goes to a friends compost, but I only keep 15-20 birds and would not want to manage...