The one I mentioned in this thread (Remember Me This Way) is the only one I can think of that I would consider trying to finish if asked. Or at least pre-SAMS, I would have considered. Nowadays probably not, but it would be in my wheelhouse. I think finishing someone else's story yourself kinda takes the fun out of it, though. I would rather enjoy it as a reader.
I hope you do get back to your story and writing in general, Steph! We miss you around here! If it gives you any hope, Rose, Dee, and I decided to resurrect 00Carter about a month ago and just finished our first episode in 9 years this week! We're not ready to post anything yet, but will have updates at some point this fall. So it can happen!