Everyone's experiences and perceptions are different. My chickens are treated as pets, and like you, I'm pretty tender hearted where my pets are concerned.
There is an adjustment period for the flock and for the rooster. I do think that chickens form attachments to each other. I also know that...
Welcome to BYC.
If understood correctly, you have a total of 10sq foot for the coop and run.
That is not nearly enough space for 13 chickens. A little tikes house is under 9sq ft. I don't see how 13 hens will fit in that.
Do you intend to sell some of the birds?