Mc's sperm should have a very precious use in the sex doll world, I mean, there must be a (sexy) scientist that can make new biological women from Mc's sperm, or at least, they could make Aisha donate some Ovum and use the sex doll uterus as a recipient, that way MC could repopulate the world not only impregnating Aisha.
Apart from that, I really would like that the pregnancy was not just a "final pregnancy ending with a pregnant sex scene", but more like "MC impregnates Aisha at some point and her belly progressively swells, then she gives birth and the story continues with her being a mother, breastfeeding her child (and MC) and raising him up", I know it's a whole lot of work just to satisfy very little demand in comparison to all the other (more demanded) stuff you want to implement in the game, but that would put your game in the "Horny Game Olympus".