I remain open, but I’m probably not going to change the ‘Rey Skywalker’ angle. I don’t want to do anything dodgy in the very final scene. My approach tends to be fairly conservative, after all.
If this was some Indy film then “just Rey,” sure. Rey calling herself Skywalker shows she has finally accepted the love of a real family (Leia is a Skywalker and her mother figure) and gives you that good feeling in the pit of your stomach. I don’t think changing it to just Rey is an improvement for this scene or as a finale as it lacks impact.