Hey the pink velvety stuff is called granulation tissue and happens to all healing tissue. It is a little painful and may bleed on touch but it indicates strong and fast healing. nothing to worry about except make sure our dog is vaccinated for rabies.
About the stray dogs carry a stick with you when you're out for a walk that is more than enough to dissuade them from coming near you. I request you to please not call the authorities and have them take the dogs away because here in India stray dogs go through hell when they are caught, neutered without adequate anaesthesia, left without post operative care on the streets, live the rest of their miserable lives weak and with infected wounds to ultimately die under some truck. Carry a stick/stones to just throw near them as they are street wise and know when to run away.