I currently have 3 roosters. All my chickens free range. I have had no problem with having roosters. I prefer them so that I can hatch eggs. None of mine have ever been mean. As long as they are raised right, I see no problem with having roosters. If they grow up together, they won’t fight so...
A couple months ago, I moved houses. We made a coop out of a room in the barn that was used for horses or cows by the previous owner. All my chickens from my old house loved the new place and were doing just fine. Then, I decided to add new chickens. I got 4 Speckled Sussex and 2 Polish hens...
I doubt there are any internal injuries. You would probably notice if so. I would isolate her until she is back to acting normal and looks okay. The chickens will peck the blood of they see any.
95-100°F and decrease the temperature every week or so. The need a wide space so they can get out of the light if they are hot. They can go outside when fully feathered. You're light is fine. Good luck with your chickens!
Chickens normally grow their feathers back in 6-8 weeks. So she'll be back to her normal self soon. In the mean time I'd put neosporin on the bad spots.
If she is blind, her pupils will be blue. I have a hen who is blind in one eye. I had to put her in a pen with my show bird and she seems to be doing just fine.