I believe Rory is more apt to follow in Christopher's footsteps than Logan is. Rory consistently has been shown to have a strong dislike of children. She's physically uncomfortable around them, and even when she watches Paris's children for her in the revival, she's definitely out of her element. The only times she seems halfway comfortable around children is when another adult is there doing the majority of the supervising. I can't see her raising a child herself, especially when she's just settling into what she wants to accomplish career-wise. I think she would try, but ultimately, unless something worked out where Logan (or another man) stepped into the picture and became the more hands-on parent, Rory would end up either handing custody over to Logan or giving her child to Lorelai to raise, since she and Luke want a child to raise together anyway. If she did try to raise the child herself, I believe Lorelai would still end up handling the bulk of the child's care for the first several years at least.