Remember how in the movies, Han always understood Chewbacca, even though his growling always kind of sounded the same?  Well, it’s hard to pull that off in a book without it coming off as exhausting.  So when Leia was hiding out on the Wookiee homeworld of Kashyyyk, Ralrra was introduced as a plot device to keep those scenes from venturing into Holiday Special territory.  Ralrra had an exceptionally convenient speech impediment that allowed him to speak basic.

At some point Hasbro was planning a Ralrra/Noghri comic pack.  Allegedly they never got as far as the tooling process, but we know that Ralrra’s at least been on their radar.  Hasrbo has done a number of Wookiee Warriors from ROTS, so it’s not new territory, and I think it would have some cross-over appeal.  Maybe Ralrracheen was at the Battle of Kashyyyk.  You can’t prove he wasn’t.