One way is to expand on her skills. Maybe she has a talent for something other than what we've seen in the original series, like being an excellent tracker or having a deep understanding of the history of certain artifacts in the Hunter x Hunter world. This new skill could open up new plotlines and interactions for her.
I don't think so. There haven't been any official announcements or indications that the HxH manga will continue. But you never know, maybe there'll be a surprise in the future.