I think he should have been in the room with the others, after Xavier's funeral and have one line, showing his opinion, in fact he should have said one line of Bobby, that in the novel is his. don't know how it is in original language, but in Spain is something like this "some of us don't have where to go".
And in the scene of the x-men, in the wall, before go to battle, he should have said something too. You know, although he has a little role in the franchise, one line per scene is just fine, showing he has an opinion and a personality.