Same about Jean-Luc and Tante. Their showing up is a must. However, I'd hate Magneto to be in this in any form. Rogneto is repulsive and the biggest stain on Gambit and Rogue's history. The less often it gets brought up the best.
On one hand, I'd like to see Remy tell off Magneto somehow. Like where Mags says something like "If you ever hurt her..." and Remy just says something cool/threatening towards him.
On the other hand, it would be nice for Rogue and Mags to just acknowledge they were a mistake and move on but I have a feeling that wouldn't be soap opera-y enough for X-Men and would get disregarded with the next writer who ships them.