Looks like a nice set up, but it is wide open. Any bird in any place can see all the other birds all of the time. You need to add some clutter into that run. Things like ladders, roosts, saw horses, small pieces of plywood, pallets, lean things up against the fence.
If you think about it, your run is basically 2 dimensional, your birds really only have the floor. You need to create usable space in the third dimension, height. This allows birds to get away from each other, it gives them more exercise, makes the run more interesting. It creates even more space as birds can get on top of and underneath a platform, be on top of a roost or underneath it.
Space and good use of space allows birds to get along much better, it makes the run more interesting. And it gives more timid birds a little more space.
But this is a nice set up. You might very well be worrying about nothing that won't solve itself with a bit of time. Be aware, keep on watching like you are, but once in a very great while, you will get a bird that just does not fit in with the flock. I always solve for peace in the flock. I would not separate them, that will make it worse.
Mrs K