The question is do each of the girls represent one kink or can they have options, for example can all the girls have a 'Pregnancy' path or other options?

Each girl represents only one kink that is set for her route. It would be nice if we could offer that kind of divergency but logistically it is not possible for our small team. We certainly encourage fan efforts if they wanted to tackle the subject of the girls getting different growths than the ones they experience in game.