I also thought about drawing out their romantic interests to concentrate on their friendship first. I thought it would be good to also have some healthy competition from Red X/Hood for Nightwing and Blackfire or Zatanna.
So Starfire is now going to be hiding in the city for a while before meeting Nightwing face to face. She's going to see him and watch him fight crime. He'll probably hear strange reports about her. She'll only reveal herself when he's in danger or one of the big guys pops up.