Cleaning, tightening, and potentially streamlining the rules they have. There are some significant sore spots such as, for example, XP as both a leveling currency and a bennie currency. It's pretty noteable, IMHO, that Invisible Sun separated these two things out.What would 'forwards' be? I assume that each new genre adds at least a few unique elements to those available to characters, right? If this is 'lateral' expansion, then what would 'forwards' really consist of? New subsystems? Newer forms of rules? I mean, basically, as was discussed up thread, its a trad system. Assuming that isn't going to change, the only other direction of expansion is into different genre/milieu/tone, so somehow producing a variant/expansion that, for example, let you run super powerful characters, etc.