just had a crazy idea. Since Laura has been in a catatonic state for so long, perhaps, the twist to "restore" GH could be that she return (longer than a stint), and she awakens, and poof! It was all in her mind (especially since we don't really know what is going through it anyway). Then Luke has a great storyline, Lulu, might be normal, and other characters are brought back??
Anyway, perhaps this is a crazy idea, but there are possibilities here!