In all honesty, no matter how much you love them I think you have some tough decisions ahead.
IMO, Your run as their primary outdoor space -in its current configuration can only really accommodate 6 adult birds. 8 if they are perfectly tempered and completely harmonious.
What you have going...
I’d have to agree that space is likely a large part of this equation.
Your run is long and narrow as well, so if you have one or more bullies in your group that width doesn’t allow for the hens who’re targets to dodge past without being accosted.
Also you might want to reappraise your feed...