Not really. While the physics aren't all-there IRL, Rain Boy's existence makes sense in-universe and has an explanation, and is relatively normal for the setting. We know why and how Martha became a brain in a jar. They play by the rules of the setting. We didn't get an explanation as to why Karma was resurrected without her leg, nor does it make sense for her to want to come back that way. Sometimes these things only make sense because of IRL reasons, like marketing or keeping a character recognizable.
That said, I can see why Laura and Wolverine would at least want to be brought back with them. And Cable #11 implied that they could have gotten rid of his virus, but chose not to.