Your coop space is sufficient, but your run is only big enough for 11 birds. And, even with adequate space in the coop, your birds may not use the coop now b/c it is too hot. IMO, crowding is your issue. Check the protein content of the treat block. If it is less than 16%, they are most likely diluting their nutrients with the block. Poor nutrition and crowding are almost always the cause of feather picking and blood letting, which if not curbed, can lead to cannibalism. You might consider converting the run to deep litter management to give them improved activity choices. Do a thread search and you will find plenty of information about how to get started.
BTW, I know it's a silly case of semantics, but word choice and use is very important when it comes to receiving the correct advice. When you say chicks, the mental image it conjures up is baby chickens, not adults. Also, if you put general location in your profile, you are more apt to receive appropriate advice.