Am I hurting my girls with the space I have?   Should I let them out all day long? even if Im not home to protect them.
It's hard to say. It's tighter than I'd be comfortable with, BUT you're not seeing any aggresive pecking, feather pulling/eating ect. AND they do get out for part of the day and even more on the weekends.
If you let them free range unsupervised you will lose birds, maybe only once in awhile, maybe most of your flock. It really depends on what the predator situation is where you live.
Mine free range during the day and are locked up at night. I'm home most of the time, but eventually I'm going to lose some birds anyhow. There have been plenty of posts about bold hawks and neighborhood dogs for me to know that is inevitable. I watched a coyote for 10 minutes this morning--never got a clear shot so he's still wandering around in the area. 
 Both my dogs HATE coyotes so while a coyote attack is still a possibility I worry more about hawks and eagles.
Ok, this got really long-winded, sometimes I gett off topic. 
With the space and number of birds you have you need to be extra vigilent about keeping the coop clean. Disease is more likely then if they had more room. Also continue to watch for the behaviours we've already talked about. If possible give them a secure daytime run--I use a 7x13 dog run with chicken wire zip tied 2' up the sides and running about 1 1/2' out and under for my quarintine coop. If you do start having problems be prepared to reduce your flock 
 
You know your birds best, just keep an eye on things. Hopefully all will go well, but be honest with yourself if it's not and take corrective action.