I think those are pretty much the only possibilities. DD could be sent down tot he 4th line to bring stability, or they'll keep Engqvist up in that spot. If Engqvist stays up then Blunden most likely goes down and we roll with Moen / Darche / Engqvist / White. If Blunden stays up it's Moen / Darche / White / Blunden.
Maybe someone else will emerge the last few preseason games but I don't think so. Palushaj has been average at best and Gallagher is still a bit young.
I think the bigger question is what the Defence will look like this season. They have a bunch of guys who are poised to make the NHL jump, and it will depend on how injuries and how they start the season in the AHL. We have Nash/Diaz/Henry/Woywitka as legitimate call-ups, so it's gonna be interesting to see how that pans out.