I have the ideas lined up for Arc 8, which may or may not be split into two as I'm bringin' this home, baby! ;)
Hmm, I guess you could consider this series a prologue, because there's so much more story to tell! :) I think if I continue it, it won't be long arcs anymore, but one-shots that give you the flavor of what is to come.
Anyway, that's way ahead in the future, as the secrets start unraveling pretty quickly in Arc 7, and all kinds of stuff breaks loose in Arc 8! :)