Can you post pictures of your setup(s)? I would let the chickens choose where they want to roost. Poop boards under the roosts go a long ways toward keeping the coop litter from being smelly and dirty. Eventually, sand will certainly be smelly and dirty as well.
What does this mean in feet by feet? Dimensions and pics would help immensely What id of bedding you use depends on how you want to manage the manure. This is about cleaning but covers my 'big picture'. -I use poop boards under roosts with thin(<1/2") layer of sand/PDZ mix, sifted daily(takes 5-10mins) into bucket going to friends compost. -Scrape big or wet poops off roost and ramps as needed. -Pine shavings on coop floor, add some occasionally, totally changed out once or twice a year, old shavings added to run. -Runs have semi-deep litter, never clean anything out, just add smaller dry materials on occasion, add larger wood chippings as needed. -Nests are bedded with straw, add some occasionally, change out if needed(broken egg). There is no odor, unless a fresh cecal has been dropped and when I open the bucket to add more poop. That's how I keep it 'clean', have not found any reason to clean 'deeper' in 5 years.
Oh, dear...the manufacturer suggests 12 birds in there? Common misconception(lie) spread by coop makers. Actual coop portion, not including nests, is only about 4x4. Space for 4 birds minimally...if following the 4/10 'rule of thumb'. Any ventilation other than those 2 round vents? Is there a way to get in there to clean and grab birds off roost for exams??