Keep an eye on it for now, if it’s small and already scabbing it’ll probably heal quite fast. But make sure it doesn’t get infected or bigger; sometimes when a wound is healing it itches, and some hedgehogs chew on it and make it worse. If it does get worse you’ll have to take her to the vet. I hope it heals quickly, and thank you!
I tend to go with my gut feeling - I want to get that “this is the one” feeling. Sometimes you see an animal and you get that feeling immediately. So I would say, get the one that feels right. As for character, one that’s not that huffy and seems curious and outgoing (but who knows, maybe you’ll fall in love with the shy one)
But besides that, check if the hedgehog is healthy; not too skinny, no runny eyes or nose, no injuries etc.